view src/eval.c @ 33566:e1e3805fcd96 v9.0.2028

patch 9.0.2028: confusing build dependencies Commit: https://github.com/vim/vim/commit/5d03525cdef5db1b1cedfa26c6f8a21aaa207ec0 Author: Yee Cheng Chin <ychin.git@gmail.com> Date: Sun Oct 15 09:50:53 2023 +0200 patch 9.0.2028: confusing build dependencies Problem: confusing build dependencies Solution: clean them up, make them parallelizable Separate vim binary and unittest dependencies, make them parallelizable Clean up make dependencies so Vim and unit test binaries only depend on the object files they need. This fixes an existing issue where after running unit tests, the Vim binary would be invalidated, which results in it having to be linked again when running script tests, even though Vim was already previously built. Make link.sh (script we use to link those binaries) generate namespaced temporary files for each app to avoid them colliding with each other. This allows `unittesttargets` to be built in parallel. These fixes are useful when using link-time-optimization as the link phase could now take minutes rather than a few seconds. closes: #13344 Signed-off-by: Christian Brabandt <cb@256bit.org> Co-authored-by: Yee Cheng Chin <ychin.git@gmail.com>
author Christian Brabandt <cb@256bit.org>
date Sun, 15 Oct 2023 10:00:03 +0200
parents fd8501e21b7d
children 4db948057fa6
line wrap: on
line source

/* vi:set ts=8 sts=4 sw=4 noet:
 *
 * VIM - Vi IMproved	by Bram Moolenaar
 *
 * Do ":help uganda"  in Vim to read copying and usage conditions.
 * Do ":help credits" in Vim to see a list of people who contributed.
 * See README.txt for an overview of the Vim source code.
 */

/*
 * eval.c: Expression evaluation.
 */
#define USING_FLOAT_STUFF

#include "vim.h"

#if defined(FEAT_EVAL) || defined(PROTO)

#ifdef VMS
# include <float.h>
#endif

#define NAMESPACE_CHAR	(char_u *)"abglstvw"

/*
 * When recursively copying lists and dicts we need to remember which ones we
 * have done to avoid endless recursiveness.  This unique ID is used for that.
 * The last bit is used for previous_funccal, ignored when comparing.
 */
static int current_copyID = 0;

static int eval2(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
static int eval3(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
static int eval4(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
static int eval5(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
static int eval6(char_u **arg, typval_T *rettv, evalarg_T *evalarg);
static int eval7(char_u **arg, typval_T *rettv, evalarg_T *evalarg, int want_string);
static int eval8(char_u **arg, typval_T *rettv, evalarg_T *evalarg, int want_string);
static int eval9(char_u **arg, typval_T *rettv, evalarg_T *evalarg, int want_string);
static int eval9_leader(typval_T *rettv, int numeric_only, char_u *start_leader, char_u **end_leaderp);

static int free_unref_items(int copyID);
static char_u *make_expanded_name(char_u *in_start, char_u *expr_start, char_u *expr_end, char_u *in_end);

/*
 * Return "n1" divided by "n2", taking care of dividing by zero.
 * If "failed" is not NULL set it to TRUE when dividing by zero fails.
 */
	varnumber_T
num_divide(varnumber_T n1, varnumber_T n2, int *failed)
{
    varnumber_T	result;

    if (n2 == 0)
    {
	if (in_vim9script())
	{
	    emsg(_(e_divide_by_zero));
	    if (failed != NULL)
		*failed = TRUE;
	}
	if (n1 == 0)
	    result = VARNUM_MIN; // similar to NaN
	else if (n1 < 0)
	    result = -VARNUM_MAX;
	else
	    result = VARNUM_MAX;
    }
    else if (n1 == VARNUM_MIN && n2 == -1)
    {
	// specific case: trying to do VARNUM_MIN / -1 results in a positive
	// number that doesn't fit in varnumber_T and causes an FPE
	result = VARNUM_MAX;
    }
    else
	result = n1 / n2;

    return result;
}

/*
 * Return "n1" modulus "n2", taking care of dividing by zero.
 * If "failed" is not NULL set it to TRUE when dividing by zero fails.
 */
	varnumber_T
num_modulus(varnumber_T n1, varnumber_T n2, int *failed)
{
    if (n2 == 0 && in_vim9script())
    {
	emsg(_(e_divide_by_zero));
	if (failed != NULL)
	    *failed = TRUE;
    }
    return (n2 == 0) ? 0 : (n1 % n2);
}

/*
 * Initialize the global and v: variables.
 */
    void
eval_init(void)
{
    evalvars_init();
    func_init();
}

#if defined(EXITFREE) || defined(PROTO)
    void
eval_clear(void)
{
    evalvars_clear();
    free_scriptnames();  // must come after evalvars_clear().
    free_locales();

    // autoloaded script names
    free_autoload_scriptnames();

    // unreferenced lists and dicts
    (void)garbage_collect(FALSE);

    // functions not garbage collected
    free_all_functions();
}
#endif

    void
fill_evalarg_from_eap(evalarg_T *evalarg, exarg_T *eap, int skip)
{
    init_evalarg(evalarg);
    evalarg->eval_flags = skip ? 0 : EVAL_EVALUATE;

    if (eap == NULL)
	return;

    evalarg->eval_cstack = eap->cstack;
    if (sourcing_a_script(eap) || eap->getline == get_list_line)
    {
	evalarg->eval_getline = eap->getline;
	evalarg->eval_cookie = eap->cookie;
    }
}

/*
 * Top level evaluation function, returning a boolean.
 * Sets "error" to TRUE if there was an error.
 * Return TRUE or FALSE.
 */
    int
eval_to_bool(
    char_u	*arg,
    int		*error,
    exarg_T	*eap,
    int		skip,	    // only parse, don't execute
    int		use_simple_function)
{
    typval_T	tv;
    varnumber_T	retval = FALSE;
    evalarg_T	evalarg;
    int		r;

    fill_evalarg_from_eap(&evalarg, eap, skip);

    if (skip)
	++emsg_skip;
    if (use_simple_function)
	r = eval0_simple_funccal(arg, &tv, eap, &evalarg);
    else
	r = eval0(arg, &tv, eap, &evalarg);
    if (r == FAIL)
	*error = TRUE;
    else
    {
	*error = FALSE;
	if (!skip)
	{
	    if (in_vim9script())
		retval = tv_get_bool_chk(&tv, error);
	    else
		retval = (tv_get_number_chk(&tv, error) != 0);
	    clear_tv(&tv);
	}
    }
    if (skip)
	--emsg_skip;
    clear_evalarg(&evalarg, eap);

    return (int)retval;
}

/*
 * Call eval1() and give an error message if not done at a lower level.
 */
    static int
eval1_emsg(char_u **arg, typval_T *rettv, exarg_T *eap)
{
    char_u	*start = *arg;
    int		ret;
    int		did_emsg_before = did_emsg;
    int		called_emsg_before = called_emsg;
    evalarg_T	evalarg;

    fill_evalarg_from_eap(&evalarg, eap, eap != NULL && eap->skip);

    ret = eval1(arg, rettv, &evalarg);
    if (ret == FAIL)
    {
	// Report the invalid expression unless the expression evaluation has
	// been cancelled due to an aborting error, an interrupt, or an
	// exception, or we already gave a more specific error.
	// Also check called_emsg for when using assert_fails().
	if (!aborting() && did_emsg == did_emsg_before
					  && called_emsg == called_emsg_before)
	    semsg(_(e_invalid_expression_str), start);
    }
    clear_evalarg(&evalarg, eap);
    return ret;
}

/*
 * Return whether a typval is a valid expression to pass to eval_expr_typval()
 * or eval_expr_to_bool().  An empty string returns FALSE;
 */
    int
eval_expr_valid_arg(typval_T *tv)
{
    return tv->v_type != VAR_UNKNOWN
	    && (tv->v_type != VAR_STRING
		  || (tv->vval.v_string != NULL && *tv->vval.v_string != NUL));
}

/*
 * When calling eval_expr_typval() many times we only need one funccall_T.
 * Returns NULL when no funccall_T is to be used.
 * When returning non-NULL remove_funccal() must be called later.
 */
    funccall_T *
eval_expr_get_funccal(typval_T *expr, typval_T *rettv)
{
    if (expr->v_type != VAR_PARTIAL)
	return NULL;

    partial_T *partial = expr->vval.v_partial;
    if (partial == NULL)
	return NULL;
    if (partial->pt_func == NULL
	    || partial->pt_func->uf_def_status == UF_NOT_COMPILED)
	return NULL;

    return create_funccal(partial->pt_func, rettv);
}

/*
 * Evaluate an expression, which can be a function, partial or string.
 * Pass arguments "argv[argc]".
 * If "want_func" is TRUE treat a string as a function name, not an expression.
 * "fc_arg" is from eval_expr_get_funccal() or NULL;
 * Return the result in "rettv" and OK or FAIL.
 */
    int
eval_expr_typval(
	typval_T    *expr,
	int	    want_func,
	typval_T    *argv,
	int	    argc,
	funccall_T  *fc_arg,
	typval_T    *rettv)
{
    char_u	*s;
    char_u	buf[NUMBUFLEN];
    funcexe_T	funcexe;

    if (expr->v_type == VAR_PARTIAL)
    {
	partial_T   *partial = expr->vval.v_partial;

	if (partial == NULL)
	    return FAIL;

	if (partial->pt_func != NULL
			  && partial->pt_func->uf_def_status != UF_NOT_COMPILED)
	{
	    funccall_T	*fc = fc_arg != NULL ? fc_arg
				     : create_funccal(partial->pt_func, rettv);
	    int		r;

	    if (fc == NULL)
		return FAIL;

	    // Shortcut to call a compiled function with minimal overhead.
	    r = call_def_function(partial->pt_func, argc, argv,
				    DEF_USE_PT_ARGV, partial, NULL, fc, rettv);
	    if (fc_arg == NULL)
		remove_funccal();
	    if (r == FAIL)
		return FAIL;
	}
	else
	{
	    s = partial_name(partial);
	    if (s == NULL || *s == NUL)
		return FAIL;
	    CLEAR_FIELD(funcexe);
	    funcexe.fe_evaluate = TRUE;
	    funcexe.fe_partial = partial;
	    if (call_func(s, -1, rettv, argc, argv, &funcexe) == FAIL)
		return FAIL;
	}
    }
    else if (expr->v_type == VAR_INSTR)
    {
	return exe_typval_instr(expr, rettv);
    }
    else if (expr->v_type == VAR_FUNC || want_func)
    {
	s = expr->v_type == VAR_FUNC
		? expr->vval.v_string
		: tv_get_string_buf_chk_strict(expr, buf, in_vim9script());
	if (s == NULL || *s == NUL)
	    return FAIL;
	CLEAR_FIELD(funcexe);
	funcexe.fe_evaluate = TRUE;
	if (call_func(s, -1, rettv, argc, argv, &funcexe) == FAIL)
	    return FAIL;
    }
    else
    {
	s = tv_get_string_buf_chk_strict(expr, buf, in_vim9script());
	if (s == NULL)
	    return FAIL;
	s = skipwhite(s);
	if (eval1_emsg(&s, rettv, NULL) == FAIL)
	    return FAIL;
	if (*skipwhite(s) != NUL)  // check for trailing chars after expr
	{
	    clear_tv(rettv);
	    semsg(_(e_invalid_expression_str), s);
	    return FAIL;
	}
    }
    return OK;
}

/*
 * Like eval_to_bool() but using a typval_T instead of a string.
 * Works for string, funcref and partial.
 */
    int
eval_expr_to_bool(typval_T *expr, int *error)
{
    typval_T	rettv;
    int		res;

    if (eval_expr_typval(expr, FALSE, NULL, 0, NULL, &rettv) == FAIL)
    {
	*error = TRUE;
	return FALSE;
    }
    res = (tv_get_bool_chk(&rettv, error) != 0);
    clear_tv(&rettv);
    return res;
}

/*
 * Top level evaluation function, returning a string.  If "skip" is TRUE,
 * only parsing to "nextcmd" is done, without reporting errors.  Return
 * pointer to allocated memory, or NULL for failure or when "skip" is TRUE.
 */
    char_u *
eval_to_string_skip(
    char_u	*arg,
    exarg_T	*eap,
    int		skip)	    // only parse, don't execute
{
    typval_T	tv;
    char_u	*retval;
    evalarg_T	evalarg;

    fill_evalarg_from_eap(&evalarg, eap, skip);
    if (skip)
	++emsg_skip;
    if (eval0(arg, &tv, eap, &evalarg) == FAIL || skip)
	retval = NULL;
    else
    {
	retval = vim_strsave(tv_get_string(&tv));
	clear_tv(&tv);
    }
    if (skip)
	--emsg_skip;
    clear_evalarg(&evalarg, eap);

    return retval;
}

/*
 * Initialize "evalarg" for use.
 */
    void
init_evalarg(evalarg_T *evalarg)
{
    CLEAR_POINTER(evalarg);
    ga_init2(&evalarg->eval_tofree_ga, sizeof(char_u *), 20);
}

/*
 * If "evalarg->eval_tofree" is not NULL free it later.
 * Caller is expected to overwrite "evalarg->eval_tofree" next.
 */
    static void
free_eval_tofree_later(evalarg_T *evalarg)
{
    if (evalarg->eval_tofree == NULL)
	return;

    if (ga_grow(&evalarg->eval_tofree_ga, 1) == OK)
	((char_u **)evalarg->eval_tofree_ga.ga_data)
	    [evalarg->eval_tofree_ga.ga_len++]
	    = evalarg->eval_tofree;
    else
	vim_free(evalarg->eval_tofree);
}

/*
 * After using "evalarg" filled from "eap": free the memory.
 */
    void
clear_evalarg(evalarg_T *evalarg, exarg_T *eap)
{
    if (evalarg == NULL)
	return;

    garray_T *etga = &evalarg->eval_tofree_ga;

    if (evalarg->eval_tofree != NULL || evalarg->eval_using_cmdline)
    {
	if (eap != NULL)
	{
	    // We may need to keep the original command line, e.g. for
	    // ":let" it has the variable names.  But we may also need
	    // the new one, "nextcmd" points into it.  Keep both.
	    vim_free(eap->cmdline_tofree);
	    eap->cmdline_tofree = *eap->cmdlinep;

	    if (evalarg->eval_using_cmdline && etga->ga_len > 0)
	    {
		// "nextcmd" points into the last line in eval_tofree_ga,
		// need to keep it around.
		--etga->ga_len;
		*eap->cmdlinep = ((char_u **)etga->ga_data)[etga->ga_len];
		vim_free(evalarg->eval_tofree);
	    }
	    else
		*eap->cmdlinep = evalarg->eval_tofree;
	}
	else
	    vim_free(evalarg->eval_tofree);
	evalarg->eval_tofree = NULL;
    }

    ga_clear_strings(etga);
    VIM_CLEAR(evalarg->eval_tofree_lambda);
}

/*
 * Skip over an expression at "*pp".
 * Return FAIL for an error, OK otherwise.
 */
    int
skip_expr(char_u **pp, evalarg_T *evalarg)
{
    typval_T	rettv;

    *pp = skipwhite(*pp);
    return eval1(pp, &rettv, evalarg);
}

/*
 * Skip over an expression at "*arg".
 * If in Vim9 script and line breaks are encountered, the lines are
 * concatenated.  "evalarg->eval_tofree" will be set accordingly.
 * "arg" is advanced to just after the expression.
 * "start" is set to the start of the expression, "end" to just after the end.
 * Also when the expression is copied to allocated memory.
 * Return FAIL for an error, OK otherwise.
 */
    int
skip_expr_concatenate(
	char_u	    **arg,
	char_u	    **start,
	char_u	    **end,
	evalarg_T   *evalarg)
{
    typval_T	rettv;
    int		res;
    int		vim9script = in_vim9script();
    garray_T    *gap = evalarg == NULL ? NULL : &evalarg->eval_ga;
    garray_T    *freegap = evalarg == NULL ? NULL : &evalarg->eval_freega;
    int		save_flags = evalarg == NULL ? 0 : evalarg->eval_flags;
    int		evaluate = evalarg == NULL
			       ? FALSE : (evalarg->eval_flags & EVAL_EVALUATE);

    if (vim9script && evaluate
	       && (evalarg->eval_cookie != NULL || evalarg->eval_cctx != NULL))
    {
	ga_init2(gap, sizeof(char_u *), 10);
	// leave room for "start"
	if (ga_grow(gap, 1) == OK)
	    ++gap->ga_len;
	ga_init2(freegap, sizeof(char_u *), 10);
    }
    *start = *arg;

    // Don't evaluate the expression.
    if (evalarg != NULL)
	evalarg->eval_flags &= ~EVAL_EVALUATE;
    *arg = skipwhite(*arg);
    res = eval1(arg, &rettv, evalarg);
    *end = *arg;
    if (evalarg != NULL)
	evalarg->eval_flags = save_flags;

    if (vim9script && evaluate
	    && (evalarg->eval_cookie != NULL || evalarg->eval_cctx != NULL))
    {
	if (evalarg->eval_ga.ga_len == 1)
	{
	    // just the one line, no need to concatenate
	    ga_clear(gap);
	    gap->ga_itemsize = 0;
	}
	else
	{
	    char_u	    *p;
	    size_t	    endoff = STRLEN(*arg);

	    // Line breaks encountered, concatenate all the lines.
	    *((char_u **)gap->ga_data) = *start;
	    p = ga_concat_strings(gap, " ");

	    // free the lines only when using getsourceline()
	    if (evalarg->eval_cookie != NULL)
	    {
		// Do not free the first line, the caller can still use it.
		*((char_u **)gap->ga_data) = NULL;
		// Do not free the last line, "arg" points into it, free it
		// later.  Also free "eval_tofree" later if needed.
		free_eval_tofree_later(evalarg);
		evalarg->eval_tofree =
				    ((char_u **)gap->ga_data)[gap->ga_len - 1];
		((char_u **)gap->ga_data)[gap->ga_len - 1] = NULL;
		ga_clear_strings(gap);
	    }
	    else
	    {
		ga_clear(gap);

		// free lines that were explicitly marked for freeing
		ga_clear_strings(freegap);
	    }

	    gap->ga_itemsize = 0;
	    if (p == NULL)
		return FAIL;
	    *start = p;
	    vim_free(evalarg->eval_tofree_lambda);
	    evalarg->eval_tofree_lambda = p;
	    // Compute "end" relative to the end.
	    *end = *start + STRLEN(*start) - endoff;
	}
    }

    return res;
}

/*
 * Convert "tv" to a string.
 * When "convert" is TRUE convert a List into a sequence of lines.
 * Returns an allocated string (NULL when out of memory).
 */
    char_u *
typval2string(typval_T *tv, int convert)
{
    garray_T	ga;
    char_u	*retval;

    if (convert && tv->v_type == VAR_LIST)
    {
	ga_init2(&ga, sizeof(char), 80);
	if (tv->vval.v_list != NULL)
	{
	    list_join(&ga, tv->vval.v_list, (char_u *)"\n", TRUE, FALSE, 0);
	    if (tv->vval.v_list->lv_len > 0)
		ga_append(&ga, NL);
	}
	ga_append(&ga, NUL);
	retval = (char_u *)ga.ga_data;
    }
    else
	retval = vim_strsave(tv_get_string(tv));
    return retval;
}

/*
 * Top level evaluation function, returning a string.  Does not handle line
 * breaks.
 * When "convert" is TRUE convert a List into a sequence of lines.
 * Return pointer to allocated memory, or NULL for failure.
 */
    char_u *
eval_to_string_eap(
    char_u	*arg,
    int		convert,
    exarg_T	*eap,
    int		use_simple_function)
{
    typval_T	tv;
    char_u	*retval;
    evalarg_T	evalarg;
    int		r;

    fill_evalarg_from_eap(&evalarg, eap, eap != NULL && eap->skip);
    if (use_simple_function)
	r = eval0_simple_funccal(arg, &tv, NULL, &evalarg);
    else
	r = eval0(arg, &tv, NULL, &evalarg);
    if (r == FAIL)
	retval = NULL;
    else
    {
	retval = typval2string(&tv, convert);
	clear_tv(&tv);
    }
    clear_evalarg(&evalarg, NULL);

    return retval;
}

    char_u *
eval_to_string(
    char_u	*arg,
    int		convert,
    int		use_simple_function)
{
    return eval_to_string_eap(arg, convert, NULL, use_simple_function);
}

/*
 * Call eval_to_string() without using current local variables and using
 * textlock.  When "use_sandbox" is TRUE use the sandbox.
 * Use legacy Vim script syntax.
 */
    char_u *
eval_to_string_safe(
    char_u	*arg,
    int		use_sandbox,
    int		keep_script_version,
    int		use_simple_function)
{
    char_u	*retval;
    funccal_entry_T funccal_entry;
    int		save_sc_version = current_sctx.sc_version;
    int		save_garbage = may_garbage_collect;

    if (!keep_script_version)
	current_sctx.sc_version = 1;
    save_funccal(&funccal_entry);
    if (use_sandbox)
	++sandbox;
    ++textlock;
    may_garbage_collect = FALSE;
    retval = eval_to_string(arg, FALSE, use_simple_function);
    if (use_sandbox)
	--sandbox;
    --textlock;
    may_garbage_collect = save_garbage;
    restore_funccal();
    current_sctx.sc_version = save_sc_version;
    return retval;
}

/*
 * Top level evaluation function, returning a number.
 * Evaluates "expr" silently.
 * Returns -1 for an error.
 */
    varnumber_T
eval_to_number(char_u *expr, int use_simple_function)
{
    typval_T	rettv;
    varnumber_T	retval;
    char_u	*p = skipwhite(expr);
    int		r = NOTDONE;

    ++emsg_off;

    if (use_simple_function)
	r = may_call_simple_func(expr, &rettv);
    if (r == NOTDONE)
	r = eval1(&p, &rettv, &EVALARG_EVALUATE);
    if (r == FAIL)
	retval = -1;
    else
    {
	retval = tv_get_number_chk(&rettv, NULL);
	clear_tv(&rettv);
    }
    --emsg_off;

    return retval;
}

/*
 * Top level evaluation function.
 * Returns an allocated typval_T with the result.
 * Returns NULL when there is an error.
 */
    typval_T *
eval_expr(char_u *arg, exarg_T *eap)
{
    return eval_expr_ext(arg, eap, FALSE);
}

    typval_T *
eval_expr_ext(char_u *arg, exarg_T *eap, int use_simple_function)
{
    typval_T	*tv;
    evalarg_T	evalarg;

    fill_evalarg_from_eap(&evalarg, eap, eap != NULL && eap->skip);

    tv = ALLOC_ONE(typval_T);
    if (tv != NULL)
    {
	int	r = NOTDONE;

	if (use_simple_function)
	    r = eval0_simple_funccal(arg, tv, eap, &evalarg);
	if (r == NOTDONE)
	    r = eval0(arg, tv, eap, &evalarg);

	if (r == FAIL)
	    VIM_CLEAR(tv);
    }

    clear_evalarg(&evalarg, eap);
    return tv;
}

/*
 * "*arg" points to what can be a function name in the form of "import.Name" or
 * "Funcref".  Return the name of the function.  Set "tofree" to something that
 * was allocated.
 * If "verbose" is FALSE no errors are given.
 * Return NULL for any failure.
 */
    static char_u *
deref_function_name(
	    char_u	**arg,
	    char_u	**tofree,
	    evalarg_T	*evalarg,
	    int		verbose)
{
    typval_T	ref;
    char_u	*name = *arg;
    int		save_flags = 0;

    ref.v_type = VAR_UNKNOWN;
    if (evalarg != NULL)
    {
	// need to evaluate this to get an import, like in "a.Func"
	save_flags = evalarg->eval_flags;
	evalarg->eval_flags |= EVAL_EVALUATE;
    }
    if (eval9(arg, &ref, evalarg, FALSE) == FAIL)
    {
	dictitem_T	*v;

	// If <SID>VarName was used it would not be found, try another way.
	v = find_var_also_in_script(name, NULL, FALSE);
	if (v == NULL)
	{
	    name = NULL;
	    goto theend;
	}
	copy_tv(&v->di_tv, &ref);
    }
    if (*skipwhite(*arg) != NUL)
    {
	if (verbose)
	    semsg(_(e_trailing_characters_str), *arg);
	name = NULL;
    }
    else if (ref.v_type == VAR_FUNC && ref.vval.v_string != NULL)
    {
	name = ref.vval.v_string;
	ref.vval.v_string = NULL;
	*tofree = name;
    }
    else if (ref.v_type == VAR_PARTIAL && ref.vval.v_partial != NULL)
    {
	if (ref.vval.v_partial->pt_argc > 0
		|| ref.vval.v_partial->pt_dict != NULL)
	{
	    if (verbose)
		emsg(_(e_cannot_use_partial_here));
	    name = NULL;
	}
	else
	{
	    name = vim_strsave(partial_name(ref.vval.v_partial));
	    *tofree = name;
	}
    }
    else
    {
	if (verbose)
	    semsg(_(e_not_callable_type_str), name);
	name = NULL;
    }

theend:
    clear_tv(&ref);
    if (evalarg != NULL)
	evalarg->eval_flags = save_flags;
    return name;
}

/*
 * Call some Vim script function and return the result in "*rettv".
 * Uses argv[0] to argv[argc - 1] for the function arguments.  argv[argc]
 * should have type VAR_UNKNOWN.
 * Returns OK or FAIL.
 */
    int
call_vim_function(
    char_u      *func,
    int		argc,
    typval_T	*argv,
    typval_T	*rettv)
{
    int		ret;
    funcexe_T	funcexe;
    char_u	*arg;
    char_u	*name;
    char_u	*tofree = NULL;
    int		ignore_errors;

    rettv->v_type = VAR_UNKNOWN;		// clear_tv() uses this
    CLEAR_FIELD(funcexe);
    funcexe.fe_firstline = curwin->w_cursor.lnum;
    funcexe.fe_lastline = curwin->w_cursor.lnum;
    funcexe.fe_evaluate = TRUE;

    // The name might be "import.Func" or "Funcref".  We don't know, we need to
    // ignore errors for an undefined name.  But we do want errors when an
    // autoload script has errors.  Guess that when there is a dot in the name
    // showing errors is the right choice.
    ignore_errors = vim_strchr(func, '.') == NULL;
    arg = func;
    if (ignore_errors)
	++emsg_off;
    name = deref_function_name(&arg, &tofree, &EVALARG_EVALUATE, FALSE);
    if (ignore_errors)
	--emsg_off;
    if (name == NULL)
	name = func;

    ret = call_func(name, -1, rettv, argc, argv, &funcexe);

    if (ret == FAIL)
	clear_tv(rettv);
    vim_free(tofree);

    return ret;
}

/*
 * Call Vim script function "func" and return the result as a string.
 * Uses "argv[0]" to "argv[argc - 1]" for the function arguments. "argv[argc]"
 * should have type VAR_UNKNOWN.
 * Returns NULL when calling the function fails.
 */
    void *
call_func_retstr(
    char_u      *func,
    int		argc,
    typval_T	*argv)
{
    typval_T	rettv;
    char_u	*retval;

    if (call_vim_function(func, argc, argv, &rettv) == FAIL)
	return NULL;

    retval = vim_strsave(tv_get_string(&rettv));
    clear_tv(&rettv);
    return retval;
}

/*
 * Call Vim script function "func" and return the result as a List.
 * Uses "argv" and "argc" as call_func_retstr().
 * Returns NULL when there is something wrong.
 * Gives an error when the returned value is not a list.
 */
    void *
call_func_retlist(
    char_u      *func,
    int		argc,
    typval_T	*argv)
{
    typval_T	rettv;

    if (call_vim_function(func, argc, argv, &rettv) == FAIL)
	return NULL;

    if (rettv.v_type != VAR_LIST)
    {
	semsg(_(e_custom_list_completion_function_does_not_return_list_but_str),
		vartype_name(rettv.v_type));
	clear_tv(&rettv);
	return NULL;
    }

    return rettv.vval.v_list;
}

#if defined(FEAT_FOLDING) || defined(PROTO)
/*
 * Evaluate "arg", which is 'foldexpr'.
 * Note: caller must set "curwin" to match "arg".
 * Returns the foldlevel, and any character preceding it in "*cp".  Doesn't
 * give error messages.
 */
    int
eval_foldexpr(win_T *wp, int *cp)
{
    char_u	*arg;
    typval_T	tv;
    varnumber_T	retval;
    char_u	*s;
    sctx_T	saved_sctx = current_sctx;
    int		use_sandbox = was_set_insecurely((char_u *)"foldexpr",
								    OPT_LOCAL);

    arg = skipwhite(wp->w_p_fde);
    current_sctx = wp->w_p_script_ctx[WV_FDE];

    ++emsg_off;
    if (use_sandbox)
	++sandbox;
    ++textlock;
    *cp = NUL;

    // Evaluate the expression.  If the expression is "FuncName()" call the
    // function directly.
    if (eval0_simple_funccal(arg, &tv, NULL, &EVALARG_EVALUATE) == FAIL)
	retval = 0;
    else
    {
	// If the result is a number, just return the number.
	if (tv.v_type == VAR_NUMBER)
	    retval = tv.vval.v_number;
	else if (tv.v_type != VAR_STRING || tv.vval.v_string == NULL)
	    retval = 0;
	else
	{
	    // If the result is a string, check if there is a non-digit before
	    // the number.
	    s = tv.vval.v_string;
	    if (*s != NUL && !VIM_ISDIGIT(*s) && *s != '-')
		*cp = *s++;
	    retval = atol((char *)s);
	}
	clear_tv(&tv);
    }
    --emsg_off;
    if (use_sandbox)
	--sandbox;
    --textlock;
    clear_evalarg(&EVALARG_EVALUATE, NULL);
    current_sctx = saved_sctx;

    return (int)retval;
}
#endif

#ifdef LOG_LOCKVAR
typedef struct flag_string_S
{
    int	    flag;
    char    *str;
} flag_string_T;

    static char *
flags_tostring(int flags, flag_string_T *_fstring, char *buf, size_t n)
{
    char *p = buf;
    *p = NUL;
    for (flag_string_T *fstring = _fstring; fstring->flag; ++fstring)
    {
	if ((fstring->flag & flags) != 0)
	{
	    size_t len = STRLEN(fstring->str);
	    if (n > p - buf + len + 7)
	    {
		STRCAT(p, fstring->str);
		p += len;
		STRCAT(p, " ");
		++p;
	    }
	    else
	    {
		STRCAT(buf, "...");
		break;
	    }
	}
    }
    return buf;
}

flag_string_T glv_flag_strings[] = {
    { GLV_QUIET,		"QUIET" },
    { GLV_NO_AUTOLOAD,		"NO_AUTOLOAD" },
    { GLV_READ_ONLY,		"READ_ONLY" },
    { GLV_NO_DECL,		"NO_DECL" },
    { GLV_COMPILING,		"COMPILING" },
    { GLV_ASSIGN_WITH_OP,	"ASSIGN_WITH_OP" },
    { GLV_PREFER_FUNC,		"PREFER_FUNC" },
    { 0,			NULL }
};
#endif

/*
 * Fill in "lp" using "root". This is used in a special case when
 * "get_lval()" parses a bare word when "lval_root" is not NULL.
 *
 * This is typically called with "lval_root" as "root". For a class, find
 * the name from lp in the class from root, fill in lval_T if found. For a
 * complex type, list/dict use it as the result; just put the root into
 * ll_tv.
 *
 * "lval_root" is a hack used during run-time/instr-execution to provide the
 * starting point for "get_lval()" to traverse a chain of indexes. In some
 * cases get_lval sees a bare name and uses this function to populate the
 * lval_T.
 *
 * For setting up "lval_root" (currently only used with lockvar)
 *	compile_lock_unlock - pushes object on stack (which becomes lval_root)
 *	execute_instructions: ISN_LOCKUNLOCK - sets lval_root from stack.
 */
    static void
fill_lval_from_lval_root(lval_T *lp, lval_root_T *lr)
{
#ifdef LOG_LOCKVAR
    ch_log(NULL, "LKVAR: fill_lval_from_lval_root(): name %s, tv %p",
						lp->ll_name, (void*)lr->lr_tv);
#endif
    if (lr->lr_tv == NULL)
	return;
    if (!lr->lr_is_arg && lr->lr_tv->v_type == VAR_CLASS)
    {
	if (lr->lr_tv->vval.v_class != NULL)
	{
	    // Special special case. Look for a bare class variable reference.
	    class_T	*cl = lr->lr_tv->vval.v_class;
	    int		m_idx;
	    ocmember_T	*m = class_member_lookup(cl, lp->ll_name,
					lp->ll_name_end - lp->ll_name, &m_idx);
	    if (m != NULL)
	    {
		// Assuming "inside class" since bare reference.
		lp->ll_class = lr->lr_tv->vval.v_class;
		lp->ll_oi = m_idx;
		lp->ll_valtype = m->ocm_type;
		lp->ll_tv = &lp->ll_class->class_members_tv[m_idx];
#ifdef LOG_LOCKVAR
		ch_log(NULL, "LKVAR:    ... class member %s.%s",
					lp->ll_class->class_name, lp->ll_name);
#endif
		return;
	    }
	}
    }

#ifdef LOG_LOCKVAR
    ch_log(NULL, "LKVAR:    ... type: %s", vartype_name(lr->lr_tv->v_type));
#endif
    lp->ll_tv = lr->lr_tv;
    lp->ll_is_root = TRUE;
}

/*
 * Check if the class has permission to access the member.
 * Returns OK or FAIL.
 */
    static int
get_lval_check_access(
    class_T	*cl_exec,   // executing class, NULL if :def or script level
    class_T	*cl,	    // class which contains the member
    ocmember_T	*om,	    // member being accessed
    char_u	*p,	    // char after member name
    int		flags)	    // GLV flags to check if writing to lval
{
#ifdef LOG_LOCKVAR
    ch_log(NULL, "LKVAR: get_lval_check_access(), cl_exec %p, cl %p, %c",
						(void*)cl_exec, (void*)cl, *p);
#endif
    if (cl_exec == NULL || cl_exec != cl)
    {
	char *msg = NULL;
	switch (om->ocm_access)
	{
	    case VIM_ACCESS_PRIVATE:
		msg = e_cannot_access_private_variable_str;
		break;
	    case VIM_ACCESS_READ:
		// If [idx] or .key following, read only OK.
		if (*p == '[' || *p == '.')
		    break;
		if ((flags & GLV_READ_ONLY) == 0)
		    msg = e_variable_is_not_writable_str;
		break;
	    case VIM_ACCESS_ALL:
		break;
	}
	if (msg != NULL)
	{
	    emsg_var_cl_define(msg, om->ocm_name, 0, cl);
	    return FAIL;
	}

    }
    return OK;
}

/*
 * Get an lval: variable, Dict item or List item that can be assigned a value
 * to: "name", "na{me}", "name[expr]", "name[expr:expr]", "name[expr][expr]",
 * "name.key", "name.key[expr]" etc.
 * Indexing only works if "name" is an existing List or Dictionary.
 * "name" points to the start of the name.
 * If "rettv" is not NULL it points to the value to be assigned.
 * "unlet" is TRUE for ":unlet": slightly different behavior when something is
 * wrong; must end in space or cmd separator.
 *
 * flags:
 *  GLV_QUIET:       do not give error messages
 *  GLV_READ_ONLY:   will not change the variable
 *  GLV_NO_AUTOLOAD: do not use script autoloading
 *
 * Returns a pointer to just after the name, including indexes.
 * When an evaluation error occurs "lp->ll_name" is NULL;
 * Returns NULL for a parsing error.  Still need to free items in "lp"!
 */
    char_u *
get_lval(
    char_u	*name,
    typval_T	*rettv,
    lval_T	*lp,
    int		unlet,
    int		skip,
    int		flags,	    // GLV_ values
    int		fne_flags)  // flags for find_name_end()
{
    char_u	*p;
    char_u	*expr_start, *expr_end;
    int		cc;
    dictitem_T	*v;
    typval_T	var1;
    typval_T	var2;
    int		empty1 = FALSE;
    char_u	*key = NULL;
    int		len;
    hashtab_T	*ht = NULL;
    int		quiet = flags & GLV_QUIET;
    int		writing = 0;
    int		vim9script = in_vim9script();
    class_T	*cl_exec = NULL;    // class that is executing, or NULL.

#ifdef LOG_LOCKVAR
    if (lval_root == NULL)
	ch_log(NULL, "LKVAR: get_lval(): name: %s, lval_root (nil)", name);
    else
	ch_log(NULL, "LKVAR: get_lval(): name: %s, lr_tv %p lr_is_arg %d",
			name, (void*)lval_root->lr_tv, lval_root->lr_is_arg);
    char buf[80];
    ch_log(NULL, "LKVAR:    ...: GLV flags: %s",
		    flags_tostring(flags, glv_flag_strings, buf, sizeof(buf)));
#endif

    // Clear everything in "lp".
    CLEAR_POINTER(lp);

    if (skip || (flags & GLV_COMPILING))
    {
	// When skipping or compiling just find the end of the name.
	lp->ll_name = name;
	lp->ll_name_end = find_name_end(name, NULL, NULL,
						      FNE_INCL_BR | fne_flags);
	return lp->ll_name_end;
    }

    // Cannot use "s:var" at the Vim9 script level.  "s: type" is OK.
    if (vim9script && at_script_level()
		  && name[0] == 's' && name[1] == ':' && !VIM_ISWHITE(name[2]))
    {
	semsg(_(e_cannot_use_s_colon_in_vim9_script_str), name);
	return NULL;
    }

    // Find the end of the name.
    p = find_name_end(name, &expr_start, &expr_end, fne_flags);
    lp->ll_name_end = p;
    if (expr_start != NULL)
    {
	// Don't expand the name when we already know there is an error.
	if (unlet && !VIM_ISWHITE(*p) && !ends_excmd(*p)
						    && *p != '[' && *p != '.')
	{
	    semsg(_(e_trailing_characters_str), p);
	    return NULL;
	}

	lp->ll_exp_name = make_expanded_name(name, expr_start, expr_end, p);
	if (lp->ll_exp_name == NULL)
	{
	    // Report an invalid expression in braces, unless the
	    // expression evaluation has been cancelled due to an
	    // aborting error, an interrupt, or an exception.
	    if (!aborting() && !quiet)
	    {
		emsg_severe = TRUE;
		semsg(_(e_invalid_argument_str), name);
		return NULL;
	    }
	}
	lp->ll_name = lp->ll_exp_name;
    }
    else
    {
	lp->ll_name = name;

	if (vim9script)
	{
	    // "a: type" is declaring variable "a" with a type, not "a:".
	    // However, "g:[key]" is indexing a dictionary.
	    if (p == name + 2 && p[-1] == ':' && *p != '[')
	    {
		--p;
		lp->ll_name_end = p;
	    }
	    if (*skipwhite(p) == ':')
	    {
		char_u	    *tp = skipwhite(p + 1);

		if (is_scoped_variable(name))
		{
		    semsg(_(e_cannot_use_type_with_this_variable_str), name);
		    return NULL;
		}
		if (VIM_ISWHITE(*p))
		{
		    semsg(_(e_no_white_space_allowed_before_colon_str), p);
		    return NULL;
		}
		if (tp == p + 1 && !quiet)
		{
		    semsg(_(e_white_space_required_after_str_str), ":", p);
		    return NULL;
		}
		if (!SCRIPT_ID_VALID(current_sctx.sc_sid))
		{
		    semsg(_(e_using_type_not_in_script_context_str), p);
		    return NULL;
		}
		if (vim9script && (flags & GLV_NO_DECL) &&
			!(flags & GLV_FOR_LOOP))
		{
		    // Using a type and not in a "var" declaration.
		    semsg(_(e_trailing_characters_str), p);
		    return NULL;
		}


		// parse the type after the name
		lp->ll_type = parse_type(&tp,
			       &SCRIPT_ITEM(current_sctx.sc_sid)->sn_type_list,
			       !quiet);
		if (lp->ll_type == NULL && !quiet)
		    return NULL;
		lp->ll_name_end = tp;
	    }
	    // TODO: check inside class?
	}
    }
    if (lp->ll_name == NULL)
	return p;

    if (*p == '.')
    {
	imported_T *import = find_imported(lp->ll_name, p - lp->ll_name, TRUE);

	if (import != NULL)
	{
	    ufunc_T *ufunc;
	    type_T *type;

	    import_check_sourced_sid(&import->imp_sid);
	    lp->ll_sid = import->imp_sid;
	    lp->ll_name = skipwhite(p + 1);
	    p = find_name_end(lp->ll_name, NULL, NULL, fne_flags);
	    lp->ll_name_end = p;

	    // check the item is exported
	    cc = *p;
	    *p = NUL;
	    if (find_exported(import->imp_sid, lp->ll_name, &ufunc, &type,
						       NULL, NULL, TRUE) == -1)
	    {
		*p = cc;
		return NULL;
	    }
	    *p = cc;
	}
    }

    // Without [idx] or .key we are done.
    if (*p != '[' && *p != '.')
    {
	if (lval_root != NULL)
	    fill_lval_from_lval_root(lp, lval_root);
	return p;
    }

    if (vim9script && lval_root != NULL)
	cl_exec = lval_root->lr_cl_exec;
    if (vim9script && lval_root != NULL && lval_root->lr_tv != NULL)
    {
	// using local variable
	lp->ll_tv = lval_root->lr_tv;
	v = NULL;
    }
    else
    {
	cc = *p;
	*p = NUL;
	// When we would write to the variable pass &ht and prevent autoload.
	writing = !(flags & GLV_READ_ONLY);
	v = find_var(lp->ll_name, writing ? &ht : NULL,
					 (flags & GLV_NO_AUTOLOAD) || writing);
	if (v == NULL && !quiet)
	    semsg(_(e_undefined_variable_str), lp->ll_name);
	*p = cc;
	if (v == NULL)
	    return NULL;
	lp->ll_tv = &v->di_tv;
    }

    if (vim9script && (flags & GLV_NO_DECL) == 0)
    {
	if (!quiet)
	    semsg(_(e_variable_already_declared_str), lp->ll_name);
	return NULL;
    }

    /*
     * Loop until no more [idx] or .key is following.
     */
    var1.v_type = VAR_UNKNOWN;
    var2.v_type = VAR_UNKNOWN;
    while (*p == '[' || (*p == '.' && p[1] != '=' && p[1] != '.'))
    {
	vartype_T v_type = lp->ll_tv->v_type;

	if (*p == '.' && v_type != VAR_DICT
		      && v_type != VAR_OBJECT
		      && v_type != VAR_CLASS)
	{
	    if (!quiet)
		semsg(_(e_dot_not_allowed_after_str_str),
						vartype_name(v_type), name);
	    return NULL;
	}
	if (v_type != VAR_LIST
		&& v_type != VAR_DICT
		&& v_type != VAR_BLOB
		&& v_type != VAR_OBJECT
		&& v_type != VAR_CLASS)
	{
	    if (!quiet)
		semsg(_(e_index_not_allowed_after_str_str),
						vartype_name(v_type), name);
	    return NULL;
	}

	// A NULL list/blob works like an empty list/blob, allocate one now.
	int r = OK;
	if (v_type == VAR_LIST && lp->ll_tv->vval.v_list == NULL)
	    r = rettv_list_alloc(lp->ll_tv);
	else if (v_type == VAR_BLOB && lp->ll_tv->vval.v_blob == NULL)
	    r = rettv_blob_alloc(lp->ll_tv);
	if (r == FAIL)
	    return NULL;

	if (lp->ll_range)
	{
	    if (!quiet)
		emsg(_(e_slice_must_come_last));
	    return NULL;
	}
#ifdef LOG_LOCKVAR
	ch_log(NULL, "LKVAR: get_lval() loop: p: %s, type: %s", p,
							vartype_name(v_type));
#endif

	if (vim9script && lp->ll_valtype == NULL
		&& v != NULL
		&& lp->ll_tv == &v->di_tv
		&& ht != NULL && ht == get_script_local_ht())
	{
	    svar_T  *sv = find_typval_in_script(lp->ll_tv, 0, TRUE);

	    // Vim9 script local variable: get the type
	    if (sv != NULL)
	    {
		lp->ll_valtype = sv->sv_type;
#ifdef LOG_LOCKVAR
		ch_log(NULL, "LKVAR:    ... loop: vim9 assign type: %s",
					vartype_name(lp->ll_valtype->tt_type));
#endif
	    }
	}

	len = -1;
	if (*p == '.')
	{
	    key = p + 1;
	    for (len = 0; ASCII_ISALNUM(key[len]) || key[len] == '_'; ++len)
		;
	    if (len == 0)
	    {
		if (!quiet)
		    emsg(_(e_cannot_use_empty_key_for_dictionary));
		return NULL;
	    }
	    p = key + len;
	}
	else
	{
	    // Get the index [expr] or the first index [expr: ].
	    p = skipwhite(p + 1);
	    if (*p == ':')
		empty1 = TRUE;
	    else
	    {
		empty1 = FALSE;
		if (eval1(&p, &var1, &EVALARG_EVALUATE) == FAIL)  // recursive!
		    return NULL;
		if (tv_get_string_chk(&var1) == NULL)
		{
		    // not a number or string
		    clear_tv(&var1);
		    return NULL;
		}
		p = skipwhite(p);
	    }

	    // Optionally get the second index [ :expr].
	    if (*p == ':')
	    {
		if (v_type == VAR_DICT)
		{
		    if (!quiet)
			emsg(_(e_cannot_slice_dictionary));
		    clear_tv(&var1);
		    return NULL;
		}
		if (rettv != NULL
			&& !(rettv->v_type == VAR_LIST
						 && rettv->vval.v_list != NULL)
			&& !(rettv->v_type == VAR_BLOB
						&& rettv->vval.v_blob != NULL))
		{
		    if (!quiet)
			emsg(_(e_slice_requires_list_or_blob_value));
		    clear_tv(&var1);
		    return NULL;
		}
		p = skipwhite(p + 1);
		if (*p == ']')
		    lp->ll_empty2 = TRUE;
		else
		{
		    lp->ll_empty2 = FALSE;
		    // recursive!
		    if (eval1(&p, &var2, &EVALARG_EVALUATE) == FAIL)
		    {
			clear_tv(&var1);
			return NULL;
		    }
		    if (tv_get_string_chk(&var2) == NULL)
		    {
			// not a number or string
			clear_tv(&var1);
			clear_tv(&var2);
			return NULL;
		    }
		}
		lp->ll_range = TRUE;
	    }
	    else
		lp->ll_range = FALSE;

	    if (*p != ']')
	    {
		if (!quiet)
		    emsg(_(e_missing_closing_square_brace));
		clear_tv(&var1);
		clear_tv(&var2);
		return NULL;
	    }

	    // Skip to past ']'.
	    ++p;
	}
#ifdef LOG_LOCKVAR
	if (len == -1)
	    ch_log(NULL, "LKVAR:    ... loop: p: %s, '[' key: %s", p,
				empty1 ? ":" : (char*)tv_get_string(&var1));
	else
	    ch_log(NULL, "LKVAR:    ... loop: p: %s, '.' key: %s", p, key);
#endif

	if (v_type == VAR_DICT)
	{
	    if (len == -1)
	    {
		// "[key]": get key from "var1"
		key = tv_get_string_chk(&var1);	// is number or string
		if (key == NULL)
		{
		    clear_tv(&var1);
		    return NULL;
		}
	    }
	    lp->ll_list = NULL;
	    lp->ll_object = NULL;
	    lp->ll_class = NULL;

	    // a NULL dict is equivalent with an empty dict
	    if (lp->ll_tv->vval.v_dict == NULL)
	    {
		lp->ll_tv->vval.v_dict = dict_alloc();
		if (lp->ll_tv->vval.v_dict == NULL)
		{
		    clear_tv(&var1);
		    return NULL;
		}
		++lp->ll_tv->vval.v_dict->dv_refcount;
	    }
	    lp->ll_dict = lp->ll_tv->vval.v_dict;

	    lp->ll_di = dict_find(lp->ll_dict, key, len);

	    // When assigning to a scope dictionary check that a function and
	    // variable name is valid (only variable name unless it is l: or
	    // g: dictionary). Disallow overwriting a builtin function.
	    if (rettv != NULL && lp->ll_dict->dv_scope != 0)
	    {
		int prevval;

		if (len != -1)
		{
		    prevval = key[len];
		    key[len] = NUL;
		}
		else
		    prevval = 0; // avoid compiler warning
		int wrong = (lp->ll_dict->dv_scope == VAR_DEF_SCOPE
			       && (rettv->v_type == VAR_FUNC
					    || rettv->v_type == VAR_PARTIAL)
			       && var_wrong_func_name(key, lp->ll_di == NULL))
			|| !valid_varname(key, -1, TRUE);
		if (len != -1)
		    key[len] = prevval;
		if (wrong)
		{
		    clear_tv(&var1);
		    return NULL;
		}
	    }

	    if (lp->ll_valtype != NULL)
		// use the type of the member
		lp->ll_valtype = lp->ll_valtype->tt_member;

	    if (lp->ll_di == NULL)
	    {
		// Can't add "v:" or "a:" variable.
		if (lp->ll_dict == get_vimvar_dict()
			 || &lp->ll_dict->dv_hashtab == get_funccal_args_ht())
		{
		    semsg(_(e_illegal_variable_name_str), name);
		    clear_tv(&var1);
		    return NULL;
		}

		// Key does not exist in dict: may need to add it.
		if (*p == '[' || *p == '.' || unlet)
		{
		    if (!quiet)
			semsg(_(e_key_not_present_in_dictionary_str), key);
		    clear_tv(&var1);
		    return NULL;
		}
		if (len == -1)
		    lp->ll_newkey = vim_strsave(key);
		else
		    lp->ll_newkey = vim_strnsave(key, len);
		clear_tv(&var1);
		if (lp->ll_newkey == NULL)
		    p = NULL;
		break;
	    }
	    // existing variable, need to check if it can be changed
	    else if ((flags & GLV_READ_ONLY) == 0
			&& (var_check_ro(lp->ll_di->di_flags, name, FALSE)
			  || var_check_lock(lp->ll_di->di_flags, name, FALSE)))
	    {
		clear_tv(&var1);
		return NULL;
	    }

	    clear_tv(&var1);
	    lp->ll_tv = &lp->ll_di->di_tv;
	}
	else if (v_type == VAR_BLOB)
	{
	    long bloblen = blob_len(lp->ll_tv->vval.v_blob);

	    /*
	     * Get the number and item for the only or first index of the List.
	     */
	    if (empty1)
		lp->ll_n1 = 0;
	    else
		// is number or string
		lp->ll_n1 = (long)tv_get_number(&var1);
	    clear_tv(&var1);

	    if (check_blob_index(bloblen, lp->ll_n1, quiet) == FAIL)
	    {
		clear_tv(&var2);
		return NULL;
	    }
	    if (lp->ll_range && !lp->ll_empty2)
	    {
		lp->ll_n2 = (long)tv_get_number(&var2);
		clear_tv(&var2);
		if (check_blob_range(bloblen, lp->ll_n1, lp->ll_n2, quiet)
								       == FAIL)
		    return NULL;
	    }
	    lp->ll_blob = lp->ll_tv->vval.v_blob;
	    lp->ll_tv = NULL;
	    break;
	}
	else if (v_type == VAR_LIST)
	{
	    /*
	     * Get the number and item for the only or first index of the List.
	     */
	    if (empty1)
		lp->ll_n1 = 0;
	    else
		// is number or string
		lp->ll_n1 = (long)tv_get_number(&var1);
	    clear_tv(&var1);

	    lp->ll_dict = NULL;
	    lp->ll_object = NULL;
	    lp->ll_class = NULL;
	    lp->ll_list = lp->ll_tv->vval.v_list;
	    lp->ll_li = check_range_index_one(lp->ll_list, &lp->ll_n1,
				     (flags & GLV_ASSIGN_WITH_OP) == 0, quiet);
	    if (lp->ll_li == NULL)
	    {
		clear_tv(&var2);
		return NULL;
	    }

	    if (lp->ll_valtype != NULL)
		// use the type of the member
		lp->ll_valtype = lp->ll_valtype->tt_member;

	    /*
	     * May need to find the item or absolute index for the second
	     * index of a range.
	     * When no index given: "lp->ll_empty2" is TRUE.
	     * Otherwise "lp->ll_n2" is set to the second index.
	     */
	    if (lp->ll_range && !lp->ll_empty2)
	    {
		lp->ll_n2 = (long)tv_get_number(&var2);
						    // is number or string
		clear_tv(&var2);
		if (check_range_index_two(lp->ll_list,
					    &lp->ll_n1, lp->ll_li,
					    &lp->ll_n2, quiet) == FAIL)
		    return NULL;
	    }

	    lp->ll_tv = &lp->ll_li->li_tv;
	}
	else  // v_type == VAR_CLASS || v_type == VAR_OBJECT
	{
	    lp->ll_dict = NULL;
	    lp->ll_list = NULL;

	    class_T *cl;
	    if (v_type == VAR_OBJECT)
	    {
		if (lp->ll_tv->vval.v_object == NULL)
		{
		    if (!quiet)
			emsg(_(e_using_null_object));
		    return NULL;
		}
	        cl = lp->ll_tv->vval.v_object->obj_class;
	        lp->ll_object = lp->ll_tv->vval.v_object;
	    }
	    else
	    {
	        cl = lp->ll_tv->vval.v_class;
	        lp->ll_object = NULL;
	    }
	    lp->ll_class = cl;

	    // TODO: what if class is NULL?
	    if (cl != NULL)
	    {
		lp->ll_valtype = NULL;

		if (flags & GLV_PREFER_FUNC)
		{
		    // First look for a function with this name.
		    // round 1: class functions (skipped for an object)
		    // round 2: object methods
		    for (int round = v_type == VAR_OBJECT ? 2 : 1;
							round <= 2; ++round)
		    {
			int	m_idx;
			ufunc_T	*fp;

			fp = method_lookup(cl,
				round == 1 ? VAR_CLASS : VAR_OBJECT,
				key, p - key, &m_idx);
			lp->ll_oi = m_idx;
			if (fp != NULL)
			{
			    lp->ll_ufunc = fp;
			    lp->ll_valtype = fp->uf_func_type;
			    break;
			}
		    }
		}

		if (lp->ll_valtype == NULL)
		{
		    int		m_idx;
		    ocmember_T	*om
			    = member_lookup(cl, v_type, key, p - key, &m_idx);
		    lp->ll_oi = m_idx;
		    if (om != NULL)
		    {
			if (get_lval_check_access(cl_exec, cl, om,
							  p, flags) == FAIL)
			    return NULL;

			lp->ll_valtype = om->ocm_type;

			if (v_type == VAR_OBJECT)
			    lp->ll_tv = ((typval_T *)(
					lp->ll_tv->vval.v_object + 1)) + m_idx;
			else
			    lp->ll_tv = &cl->class_members_tv[m_idx];
		    }
		}

		if (lp->ll_valtype == NULL)
		{
		    member_not_found_msg(cl, v_type, key, p - key);
		    return NULL;
		}
	    }
	}
    }

    clear_tv(&var1);
    lp->ll_name_end = p;
    return p;
}

/*
 * Clear lval "lp" that was filled by get_lval().
 */
    void
clear_lval(lval_T *lp)
{
    vim_free(lp->ll_exp_name);
    vim_free(lp->ll_newkey);
}

/*
 * Set a variable that was parsed by get_lval() to "rettv".
 * "endp" points to just after the parsed name.
 * "op" is NULL, "+" for "+=", "-" for "-=", "*" for "*=", "/" for "/=",
 * "%" for "%=", "." for ".=" or "=" for "=".
 */
    void
set_var_lval(
    lval_T	*lp,
    char_u	*endp,
    typval_T	*rettv,
    int		copy,
    int		flags,	    // ASSIGN_CONST, ASSIGN_NO_DECL
    char_u	*op,
    int		var_idx)    // index for "let [a, b] = list"
{
    int		cc;
    dictitem_T	*di;

    if (lp->ll_tv == NULL)
    {
	cc = *endp;
	*endp = NUL;
	if (in_vim9script() && check_reserved_name(lp->ll_name, FALSE) == FAIL)
	    return;

	if (lp->ll_blob != NULL)
	{
	    int	    error = FALSE, val;

	    if (op != NULL && *op != '=')
	    {
		semsg(_(e_wrong_variable_type_for_str_equal), op);
		return;
	    }
	    if (value_check_lock(lp->ll_blob->bv_lock, lp->ll_name, FALSE))
		return;

	    if (lp->ll_range && rettv->v_type == VAR_BLOB)
	    {
		if (lp->ll_empty2)
		    lp->ll_n2 = blob_len(lp->ll_blob) - 1;

		if (blob_set_range(lp->ll_blob, lp->ll_n1, lp->ll_n2,
								rettv) == FAIL)
		    return;
	    }
	    else
	    {
		val = (int)tv_get_number_chk(rettv, &error);
		if (!error)
		    blob_set_append(lp->ll_blob, lp->ll_n1, val);
	    }
	}
	else if (op != NULL && *op != '=')
	{
	    typval_T tv;

	    if ((flags & (ASSIGN_CONST | ASSIGN_FINAL))
					     && (flags & ASSIGN_FOR_LOOP) == 0)
	    {
		emsg(_(e_cannot_modify_existing_variable));
		*endp = cc;
		return;
	    }

	    // handle +=, -=, *=, /=, %= and .=
	    di = NULL;
	    if (eval_variable(lp->ll_name, (int)STRLEN(lp->ll_name),
				 lp->ll_sid, &tv, &di, EVAL_VAR_VERBOSE) == OK)
	    {
		if ((di == NULL
			 || (!var_check_ro(di->di_flags, lp->ll_name, FALSE)
			   && !tv_check_lock(&di->di_tv, lp->ll_name, FALSE)))
			&& tv_op(&tv, rettv, op) == OK)
		    set_var_const(lp->ll_name, lp->ll_sid, NULL, &tv, FALSE,
							    ASSIGN_NO_DECL, 0);
		clear_tv(&tv);
	    }
	}
	else
	{
	    if (lp->ll_type != NULL && check_typval_arg_type(lp->ll_type, rettv,
							      NULL, 0) == FAIL)
		return;
	    set_var_const(lp->ll_name, lp->ll_sid, lp->ll_type, rettv, copy,
							       flags, var_idx);
	}
	*endp = cc;
    }
    else if (value_check_lock(lp->ll_newkey == NULL
		? lp->ll_tv->v_lock
		: lp->ll_tv->vval.v_dict->dv_lock, lp->ll_name, FALSE))
	;
    else if (lp->ll_range)
    {
	if ((flags & (ASSIGN_CONST | ASSIGN_FINAL))
					     && (flags & ASSIGN_FOR_LOOP) == 0)
	{
	    emsg(_(e_cannot_lock_range));
	    return;
	}

	(void)list_assign_range(lp->ll_list, rettv->vval.v_list,
			 lp->ll_n1, lp->ll_n2, lp->ll_empty2, op, lp->ll_name);
    }
    else
    {
	/*
	 * Assign to a List, Dictionary or Object item.
	 */
	if ((flags & (ASSIGN_CONST | ASSIGN_FINAL))
					     && (flags & ASSIGN_FOR_LOOP) == 0)
	{
	    emsg(_(e_cannot_lock_list_or_dict));
	    return;
	}

	if (lp->ll_valtype != NULL
		    && check_typval_arg_type(lp->ll_valtype, rettv,
							      NULL, 0) == FAIL)
	    return;

	if (lp->ll_newkey != NULL)
	{
	    if (op != NULL && *op != '=')
	    {
		semsg(_(e_key_not_present_in_dictionary_str), lp->ll_newkey);
		return;
	    }
	    if (dict_wrong_func_name(lp->ll_tv->vval.v_dict, rettv,
								lp->ll_newkey))
		return;

	    // Need to add an item to the Dictionary.
	    di = dictitem_alloc(lp->ll_newkey);
	    if (di == NULL)
		return;
	    if (dict_add(lp->ll_tv->vval.v_dict, di) == FAIL)
	    {
		vim_free(di);
		return;
	    }
	    lp->ll_tv = &di->di_tv;
	}
	else if (op != NULL && *op != '=')
	{
	    tv_op(lp->ll_tv, rettv, op);
	    return;
	}
	else
	    clear_tv(lp->ll_tv);

	/*
	 * Assign the value to the variable or list item.
	 */
	if (copy)
	    copy_tv(rettv, lp->ll_tv);
	else
	{
	    *lp->ll_tv = *rettv;
	    lp->ll_tv->v_lock = 0;
	    init_tv(rettv);
	}
    }
}

/*
 * Handle "tv1 += tv2", "tv1 -= tv2", "tv1 *= tv2", "tv1 /= tv2", "tv1 %= tv2"
 * and "tv1 .= tv2"
 * Returns OK or FAIL.
 */
    int
tv_op(typval_T *tv1, typval_T *tv2, char_u *op)
{
    varnumber_T	n;
    char_u	numbuf[NUMBUFLEN];
    char_u	*s;
    int		failed = FALSE;

    // Can't do anything with a Funcref or Dict on the right.
    // v:true and friends only work with "..=".
    if (tv2->v_type != VAR_FUNC && tv2->v_type != VAR_DICT
		    && ((tv2->v_type != VAR_BOOL && tv2->v_type != VAR_SPECIAL)
								|| *op == '.'))
    {
	switch (tv1->v_type)
	{
	    case VAR_UNKNOWN:
	    case VAR_ANY:
	    case VAR_VOID:
	    case VAR_DICT:
	    case VAR_FUNC:
	    case VAR_PARTIAL:
	    case VAR_BOOL:
	    case VAR_SPECIAL:
	    case VAR_JOB:
	    case VAR_CHANNEL:
	    case VAR_INSTR:
	    case VAR_CLASS:
	    case VAR_OBJECT:
		break;

	    case VAR_BLOB:
		if (*op != '+' || tv2->v_type != VAR_BLOB)
		    break;
		// BLOB += BLOB
		if (tv1->vval.v_blob != NULL && tv2->vval.v_blob != NULL)
		{
		    blob_T  *b1 = tv1->vval.v_blob;
		    blob_T  *b2 = tv2->vval.v_blob;
		    int	i, len = blob_len(b2);
		    for (i = 0; i < len; i++)
			ga_append(&b1->bv_ga, blob_get(b2, i));
		}
		return OK;

	    case VAR_LIST:
		if (*op != '+' || tv2->v_type != VAR_LIST)
		    break;
		// List += List
		if (tv2->vval.v_list != NULL)
		{
		    if (tv1->vval.v_list == NULL)
		    {
			tv1->vval.v_list = tv2->vval.v_list;
			++tv1->vval.v_list->lv_refcount;
		    }
		    else
			list_extend(tv1->vval.v_list, tv2->vval.v_list, NULL);
		}
		return OK;

	    case VAR_NUMBER:
	    case VAR_STRING:
		if (tv2->v_type == VAR_LIST)
		    break;
		if (vim_strchr((char_u *)"+-*/%", *op) != NULL)
		{
		    // nr += nr , nr -= nr , nr *=nr , nr /= nr , nr %= nr
		    n = tv_get_number(tv1);
		    if (tv2->v_type == VAR_FLOAT)
		    {
			float_T f = n;

			if (*op == '%')
			    break;
			switch (*op)
			{
			    case '+': f += tv2->vval.v_float; break;
			    case '-': f -= tv2->vval.v_float; break;
			    case '*': f *= tv2->vval.v_float; break;
			    case '/': f /= tv2->vval.v_float; break;
			}
			clear_tv(tv1);
			tv1->v_type = VAR_FLOAT;
			tv1->vval.v_float = f;
		    }
		    else
		    {
			switch (*op)
			{
			    case '+': n += tv_get_number(tv2); break;
			    case '-': n -= tv_get_number(tv2); break;
			    case '*': n *= tv_get_number(tv2); break;
			    case '/': n = num_divide(n, tv_get_number(tv2),
							       &failed); break;
			    case '%': n = num_modulus(n, tv_get_number(tv2),
							       &failed); break;
			}
			clear_tv(tv1);
			tv1->v_type = VAR_NUMBER;
			tv1->vval.v_number = n;
		    }
		}
		else
		{
		    if (tv2->v_type == VAR_FLOAT)
			break;

		    // str .= str
		    s = tv_get_string(tv1);
		    s = concat_str(s, tv_get_string_buf(tv2, numbuf));
		    clear_tv(tv1);
		    tv1->v_type = VAR_STRING;
		    tv1->vval.v_string = s;
		}
		return failed ? FAIL : OK;

	    case VAR_FLOAT:
		{
		    float_T f;

		    if (*op == '%' || *op == '.'
				   || (tv2->v_type != VAR_FLOAT
				    && tv2->v_type != VAR_NUMBER
				    && tv2->v_type != VAR_STRING))
			break;
		    if (tv2->v_type == VAR_FLOAT)
			f = tv2->vval.v_float;
		    else
			f = tv_get_number(tv2);
		    switch (*op)
		    {
			case '+': tv1->vval.v_float += f; break;
			case '-': tv1->vval.v_float -= f; break;
			case '*': tv1->vval.v_float *= f; break;
			case '/': tv1->vval.v_float /= f; break;
		    }
		}
		return OK;
	}
    }

    semsg(_(e_wrong_variable_type_for_str_equal), op);
    return FAIL;
}

/*
 * Evaluate the expression used in a ":for var in expr" command.
 * "arg" points to "var".
 * Set "*errp" to TRUE for an error, FALSE otherwise;
 * Return a pointer that holds the info.  Null when there is an error.
 */
    void *
eval_for_line(
    char_u	*arg,
    int		*errp,
    exarg_T	*eap,
    evalarg_T	*evalarg)
{
    forinfo_T	*fi;
    char_u	*var_list_end;
    char_u	*expr;
    typval_T	tv;
    list_T	*l;
    int		skip = !(evalarg->eval_flags & EVAL_EVALUATE);

    *errp = TRUE;	// default: there is an error

    fi = ALLOC_CLEAR_ONE(forinfo_T);
    if (fi == NULL)
	return NULL;

    var_list_end = skip_var_list(arg, TRUE, &fi->fi_varcount,
						     &fi->fi_semicolon, FALSE);
    if (var_list_end == NULL)
	return fi;

    expr = skipwhite_and_linebreak(var_list_end, evalarg);
    if (expr[0] != 'i' || expr[1] != 'n'
				  || !(expr[2] == NUL || VIM_ISWHITE(expr[2])))
    {
	if (in_vim9script() && *expr == ':' && expr != var_list_end)
	    semsg(_(e_no_white_space_allowed_before_colon_str), expr);
	else
	    emsg(_(e_missing_in_after_for));
	return fi;
    }

    if (skip)
	++emsg_skip;
    expr = skipwhite_and_linebreak(expr + 2, evalarg);
    if (eval0(expr, &tv, eap, evalarg) == OK)
    {
	*errp = FALSE;
	if (!skip)
	{
	    if (tv.v_type == VAR_LIST)
	    {
		l = tv.vval.v_list;
		if (l == NULL)
		{
		    // a null list is like an empty list: do nothing
		    clear_tv(&tv);
		}
		else
		{
		    // Need a real list here.
		    CHECK_LIST_MATERIALIZE(l);

		    // No need to increment the refcount, it's already set for
		    // the list being used in "tv".
		    fi->fi_list = l;
		    list_add_watch(l, &fi->fi_lw);
		    fi->fi_lw.lw_item = l->lv_first;
		}
	    }
	    else if (tv.v_type == VAR_BLOB)
	    {
		fi->fi_bi = 0;
		if (tv.vval.v_blob != NULL)
		{
		    typval_T btv;

		    // Make a copy, so that the iteration still works when the
		    // blob is changed.
		    blob_copy(tv.vval.v_blob, &btv);
		    fi->fi_blob = btv.vval.v_blob;
		}
		clear_tv(&tv);
	    }
	    else if (tv.v_type == VAR_STRING)
	    {
		fi->fi_byte_idx = 0;
		fi->fi_string = tv.vval.v_string;
		tv.vval.v_string = NULL;
		if (fi->fi_string == NULL)
		    fi->fi_string = vim_strsave((char_u *)"");
	    }
	    else
	    {
		emsg(_(e_string_list_or_blob_required));
		clear_tv(&tv);
	    }
	}
    }
    if (skip)
	--emsg_skip;
    fi->fi_break_count = evalarg->eval_break_count;

    return fi;
}

/*
 * Used when looping over a :for line, skip the "in expr" part.
 */
    void
skip_for_lines(void *fi_void, evalarg_T *evalarg)
{
    forinfo_T	*fi = (forinfo_T *)fi_void;
    int		i;

    for (i = 0; i < fi->fi_break_count; ++i)
	eval_next_line(NULL, evalarg);
}

/*
 * Use the first item in a ":for" list.  Advance to the next.
 * Assign the values to the variable (list).  "arg" points to the first one.
 * Return TRUE when a valid item was found, FALSE when at end of list or
 * something wrong.
 */
    int
next_for_item(void *fi_void, char_u *arg)
{
    forinfo_T	*fi = (forinfo_T *)fi_void;
    int		result;
    int		flag = ASSIGN_FOR_LOOP | (in_vim9script()
			 ? (ASSIGN_FINAL
			     // first round: error if variable exists
			     | (fi->fi_bi == 0 ? 0 : ASSIGN_DECL)
			     | ASSIGN_NO_MEMBER_TYPE
			     | ASSIGN_UPDATE_BLOCK_ID)
			 : 0);
    listitem_T	*item;
    int		skip_assign = in_vim9script() && arg[0] == '_'
						      && !eval_isnamec(arg[1]);

    if (fi->fi_blob != NULL)
    {
	typval_T	tv;

	if (fi->fi_bi >= blob_len(fi->fi_blob))
	    return FALSE;
	tv.v_type = VAR_NUMBER;
	tv.v_lock = VAR_FIXED;
	tv.vval.v_number = blob_get(fi->fi_blob, fi->fi_bi);
	++fi->fi_bi;
	if (skip_assign)
	    return TRUE;
	return ex_let_vars(arg, &tv, TRUE, fi->fi_semicolon,
					    fi->fi_varcount, flag, NULL) == OK;
    }

    if (fi->fi_string != NULL)
    {
	typval_T	tv;
	int		len;

	len = mb_ptr2len(fi->fi_string + fi->fi_byte_idx);
	if (len == 0)
	    return FALSE;
	tv.v_type = VAR_STRING;
	tv.v_lock = VAR_FIXED;
	tv.vval.v_string = vim_strnsave(fi->fi_string + fi->fi_byte_idx, len);
	fi->fi_byte_idx += len;
	++fi->fi_bi;
	if (skip_assign)
	    result = TRUE;
	else
	    result = ex_let_vars(arg, &tv, TRUE, fi->fi_semicolon,
					    fi->fi_varcount, flag, NULL) == OK;
	vim_free(tv.vval.v_string);
	return result;
    }

    item = fi->fi_lw.lw_item;
    if (item == NULL)
	result = FALSE;
    else
    {
	fi->fi_lw.lw_item = item->li_next;
	++fi->fi_bi;
	if (skip_assign)
	    result = TRUE;
	else
	    result = (ex_let_vars(arg, &item->li_tv, TRUE, fi->fi_semicolon,
					   fi->fi_varcount, flag, NULL) == OK);
    }
    return result;
}

/*
 * Free the structure used to store info used by ":for".
 */
    void
free_for_info(void *fi_void)
{
    forinfo_T    *fi = (forinfo_T *)fi_void;

    if (fi == NULL)
	return;
    if (fi->fi_list != NULL)
    {
	list_rem_watch(fi->fi_list, &fi->fi_lw);
	list_unref(fi->fi_list);
    }
    else if (fi->fi_blob != NULL)
	blob_unref(fi->fi_blob);
    else
	vim_free(fi->fi_string);
    vim_free(fi);
}

    void
set_context_for_expression(
    expand_T	*xp,
    char_u	*arg,
    cmdidx_T	cmdidx)
{
    int		has_expr = cmdidx != CMD_let && cmdidx != CMD_var;
    int		c;
    char_u	*p;

    if (cmdidx == CMD_let || cmdidx == CMD_var
				 || cmdidx == CMD_const || cmdidx == CMD_final)
    {
	xp->xp_context = EXPAND_USER_VARS;
	if (vim_strpbrk(arg, (char_u *)"\"'+-*/%.=!?~|&$([<>,#") == NULL)
	{
	    // ":let var1 var2 ...": find last space.
	    for (p = arg + STRLEN(arg); p >= arg; )
	    {
		xp->xp_pattern = p;
		MB_PTR_BACK(arg, p);
		if (VIM_ISWHITE(*p))
		    break;
	    }
	    return;
	}
    }
    else
	xp->xp_context = cmdidx == CMD_call ? EXPAND_FUNCTIONS
							  : EXPAND_EXPRESSION;
    while ((xp->xp_pattern = vim_strpbrk(arg,
				  (char_u *)"\"'+-*/%.=!?~|&$([<>,#")) != NULL)
    {
	c = *xp->xp_pattern;
	if (c == '&')
	{
	    c = xp->xp_pattern[1];
	    if (c == '&')
	    {
		++xp->xp_pattern;
		xp->xp_context = has_expr ? EXPAND_EXPRESSION : EXPAND_NOTHING;
	    }
	    else if (c != ' ')
	    {
		xp->xp_context = EXPAND_SETTINGS;
		if ((c == 'l' || c == 'g') && xp->xp_pattern[2] == ':')
		    xp->xp_pattern += 2;

	    }
	}
	else if (c == '$')
	{
	    // environment variable
	    xp->xp_context = EXPAND_ENV_VARS;
	}
	else if (c == '=')
	{
	    has_expr = TRUE;
	    xp->xp_context = EXPAND_EXPRESSION;
	}
	else if (c == '#'
		&& xp->xp_context == EXPAND_EXPRESSION)
	{
	    // Autoload function/variable contains '#'.
	    break;
	}
	else if ((c == '<' || c == '#')
		&& xp->xp_context == EXPAND_FUNCTIONS
		&& vim_strchr(xp->xp_pattern, '(') == NULL)
	{
	    // Function name can start with "<SNR>" and contain '#'.
	    break;
	}
	else if (has_expr)
	{
	    if (c == '"')	    // string
	    {
		while ((c = *++xp->xp_pattern) != NUL && c != '"')
		    if (c == '\\' && xp->xp_pattern[1] != NUL)
			++xp->xp_pattern;
		xp->xp_context = EXPAND_NOTHING;
	    }
	    else if (c == '\'')	    // literal string
	    {
		// Trick: '' is like stopping and starting a literal string.
		while ((c = *++xp->xp_pattern) != NUL && c != '\'')
		    /* skip */ ;
		xp->xp_context = EXPAND_NOTHING;
	    }
	    else if (c == '|')
	    {
		if (xp->xp_pattern[1] == '|')
		{
		    ++xp->xp_pattern;
		    xp->xp_context = EXPAND_EXPRESSION;
		}
		else
		    xp->xp_context = EXPAND_COMMANDS;
	    }
	    else
		xp->xp_context = EXPAND_EXPRESSION;
	}
	else
	    // Doesn't look like something valid, expand as an expression
	    // anyway.
	    xp->xp_context = EXPAND_EXPRESSION;
	arg = xp->xp_pattern;
	if (*arg != NUL)
	    while ((c = *++arg) != NUL && (c == ' ' || c == '\t'))
		/* skip */ ;
    }

    // ":exe one two" completes "two"
    if ((cmdidx == CMD_execute
		|| cmdidx == CMD_echo
		|| cmdidx == CMD_echon
		|| cmdidx == CMD_echomsg
		|| cmdidx == CMD_echowindow)
	    && xp->xp_context == EXPAND_EXPRESSION)
    {
	for (;;)
	{
	    char_u *n = skiptowhite(arg);

	    if (n == arg || IS_WHITE_OR_NUL(*skipwhite(n)))
		break;
	    arg = skipwhite(n);
	}
    }

    xp->xp_pattern = arg;
}

/*
 * Return TRUE if "pat" matches "text".
 * Does not use 'cpo' and always uses 'magic'.
 */
    int
pattern_match(char_u *pat, char_u *text, int ic)
{
    int		matches = FALSE;
    char_u	*save_cpo;
    regmatch_T	regmatch;

    // avoid 'l' flag in 'cpoptions'
    save_cpo = p_cpo;
    p_cpo = empty_option;
    regmatch.regprog = vim_regcomp(pat, RE_MAGIC + RE_STRING);
    if (regmatch.regprog != NULL)
    {
	regmatch.rm_ic = ic;
	matches = vim_regexec_nl(&regmatch, text, (colnr_T)0);
	vim_regfree(regmatch.regprog);
    }
    p_cpo = save_cpo;
    return matches;
}

/*
 * Handle a name followed by "(".  Both for just "name(arg)" and for
 * "expr->name(arg)".
 * Returns OK or FAIL.
 */
    static int
eval_func(
	char_u	    **arg,	// points to "(", will be advanced
	evalarg_T   *evalarg,
	char_u	    *name,
	int	    name_len,
	typval_T    *rettv,
	int	    flags,
	typval_T    *basetv)	// "expr" for "expr->name(arg)"
{
    int		evaluate = flags & EVAL_EVALUATE;
    char_u	*s = name;
    int		len = name_len;
    partial_T	*partial;
    int		ret = OK;
    type_T	*type = NULL;
    int		found_var = FALSE;

    if (!evaluate)
	check_vars(s, len);

    // If "s" is the name of a variable of type VAR_FUNC
    // use its contents.
    s = deref_func_name(s, &len, &partial,
		 in_vim9script() ? &type : NULL, !evaluate, FALSE, &found_var);

    // Need to make a copy, in case evaluating the arguments makes
    // the name invalid.
    s = vim_strsave(s);
    if (s == NULL || (evaluate && *s == NUL))
	ret = FAIL;
    else
    {
	funcexe_T funcexe;

	// Invoke the function.
	CLEAR_FIELD(funcexe);
	funcexe.fe_firstline = curwin->w_cursor.lnum;
	funcexe.fe_lastline = curwin->w_cursor.lnum;
	funcexe.fe_evaluate = evaluate;
	funcexe.fe_partial = partial;
	funcexe.fe_basetv = basetv;
	funcexe.fe_check_type = type;
	funcexe.fe_found_var = found_var;
	ret = get_func_tv(s, len, rettv, arg, evalarg, &funcexe);
    }
    vim_free(s);

    // If evaluate is FALSE rettv->v_type was not set in
    // get_func_tv, but it's needed in handle_subscript() to parse
    // what follows. So set it here.
    if (rettv->v_type == VAR_UNKNOWN && !evaluate && **arg == '(')
    {
	rettv->vval.v_string = NULL;
	rettv->v_type = VAR_FUNC;
    }

    // Stop the expression evaluation when immediately
    // aborting on error, or when an interrupt occurred or
    // an exception was thrown but not caught.
    if (evaluate && aborting())
    {
	if (ret == OK)
	    clear_tv(rettv);
	ret = FAIL;
    }
    return ret;
}

/*
 * After a NL, skip over empty lines and comment-only lines.
 */
    static char_u *
newline_skip_comments(char_u *arg)
{
    char_u *p = arg + 1;

    for (;;)
    {
	p = skipwhite(p);

	if (*p == NUL)
	    break;
	if (vim9_comment_start(p))
	{
	    char_u *nl = vim_strchr(p, NL);

	    if (nl == NULL)
		    break;
	    p = nl;
	}
	if (*p != NL)
	    break;
	++p;  // skip another NL
    }
    return p;
}

/*
 * Get the next line source line without advancing.  But do skip over comment
 * lines.
 * Only called for Vim9 script.
 */
    static char_u *
getline_peek_skip_comments(evalarg_T *evalarg)
{
    for (;;)
    {
	char_u *next = getline_peek(evalarg->eval_getline,
							 evalarg->eval_cookie);
	char_u *p;

	if (next == NULL)
	    break;
	p = skipwhite(next);
	if (*p != NUL && !vim9_comment_start(p))
	    return next;
	if (eval_next_line(NULL, evalarg) == NULL)
	    break;
    }
    return NULL;
}

/*
 * If inside Vim9 script, "arg" points to the end of a line (ignoring a #
 * comment) and there is a next line, return the next line (skipping blanks)
 * and set "getnext".
 * Otherwise return the next non-white at or after "arg" and set "getnext" to
 * FALSE.
 * "arg" must point somewhere inside a line, not at the start.
 */
    char_u *
eval_next_non_blank(char_u *arg, evalarg_T *evalarg, int *getnext)
{
    char_u *p = skipwhite(arg);

    *getnext = FALSE;
    if (in_vim9script()
	    && evalarg != NULL
	    && (evalarg->eval_cookie != NULL || evalarg->eval_cctx != NULL
								   || *p == NL)
	    && (*p == NUL || *p == NL
			     || (vim9_comment_start(p) && VIM_ISWHITE(p[-1]))))
    {
	char_u *next;

	if (*p == NL)
	    next = newline_skip_comments(p);
	else if (evalarg->eval_cookie != NULL)
	    next = getline_peek_skip_comments(evalarg);
	else
	    next = peek_next_line_from_context(evalarg->eval_cctx);

	if (next != NULL)
	{
	    *getnext = *p != NL;
	    return skipwhite(next);
	}
    }
    return p;
}

/*
 * To be called after eval_next_non_blank() sets "getnext" to TRUE.
 * Only called for Vim9 script.
 */
    char_u *
eval_next_line(char_u *arg, evalarg_T *evalarg)
{
    garray_T	*gap = &evalarg->eval_ga;
    char_u	*line;

    if (arg != NULL)
    {
	if (*arg == NL)
	    return newline_skip_comments(arg);
	// Truncate before a trailing comment, so that concatenating the lines
	// won't turn the rest into a comment.
	if (*skipwhite(arg) == '#')
	    *arg = NUL;
    }

    if (evalarg->eval_cookie != NULL)
	line = evalarg->eval_getline(0, evalarg->eval_cookie, 0,
							   GETLINE_CONCAT_ALL);
    else
	line = next_line_from_context(evalarg->eval_cctx, TRUE);
    if (line == NULL)
	return NULL;

    ++evalarg->eval_break_count;
    if (gap->ga_itemsize > 0 && ga_grow(gap, 1) == OK)
    {
	char_u *p = skipwhite(line);

	// Going to concatenate the lines after parsing.  For an empty or
	// comment line use an empty string.
	if (*p == NUL || vim9_comment_start(p))
	{
	    vim_free(line);
	    line = vim_strsave((char_u *)"");
	}

	((char_u **)gap->ga_data)[gap->ga_len] = line;
	++gap->ga_len;
    }
    else if (evalarg->eval_cookie != NULL)
    {
	free_eval_tofree_later(evalarg);
	evalarg->eval_tofree = line;
    }

    // Advanced to the next line, "arg" no longer points into the previous
    // line.
    evalarg->eval_using_cmdline = FALSE;
    return skipwhite(line);
}

/*
 * Call eval_next_non_blank() and get the next line if needed.
 */
    char_u *
skipwhite_and_linebreak(char_u *arg, evalarg_T *evalarg)
{
    int	    getnext;
    char_u  *p = skipwhite_and_nl(arg);

    if (evalarg == NULL)
	return skipwhite(arg);
    eval_next_non_blank(p, evalarg, &getnext);
    if (getnext)
	return eval_next_line(arg, evalarg);
    return p;
}

/*
 * The "eval" functions have an "evalarg" argument: When NULL or
 * "evalarg->eval_flags" does not have EVAL_EVALUATE, then the argument is only
 * parsed but not executed.  The functions may return OK, but the rettv will be
 * of type VAR_UNKNOWN.  The functions still returns FAIL for a syntax error.
 */

/*
 * Handle zero level expression.
 * This calls eval1() and handles error message and nextcmd.
 * Put the result in "rettv" when returning OK and "evaluate" is TRUE.
 * Note: "rettv.v_lock" is not set.
 * "evalarg" can be NULL, EVALARG_EVALUATE or a pointer.
 * Return OK or FAIL.
 */
    int
eval0(
    char_u	*arg,
    typval_T	*rettv,
    exarg_T	*eap,
    evalarg_T	*evalarg)
{
    return eval0_retarg(arg, rettv, eap, evalarg, NULL);
}

/*
 * If "arg" is a simple function call without arguments then call it and return
 * the result.  Otherwise return NOTDONE.
 */
    int
may_call_simple_func(
    char_u	*arg,
    typval_T	*rettv)
{
    char_u  *parens = (char_u *)strstr((char *)arg, "()");
    int	    r = NOTDONE;

    // If the expression is "FuncName()" then we can skip a lot of overhead.
    if (parens != NULL && *skipwhite(parens + 2) == NUL)
    {
	char_u *p = STRNCMP(arg, "<SNR>", 5) == 0 ? skipdigits(arg + 5) : arg;

	if (to_name_end(p, TRUE) == parens)
	    r = call_simple_func(arg, (int)(parens - arg), rettv);
    }
    return r;
}

/*
 * Handle zero level expression with optimization for a simple function call.
 * Same arguments and return value as eval0().
 */
    int
eval0_simple_funccal(
    char_u	*arg,
    typval_T	*rettv,
    exarg_T	*eap,
    evalarg_T	*evalarg)
{
    int	    r = may_call_simple_func(arg, rettv);

    if (r == NOTDONE)
	r = eval0_retarg(arg, rettv, eap, evalarg, NULL);
    return r;
}

/*
 * Like eval0() but when "retarg" is not NULL store the pointer to after the
 * expression and don't check what comes after the expression.
 */
    int
eval0_retarg(
    char_u	*arg,
    typval_T	*rettv,
    exarg_T	*eap,
    evalarg_T	*evalarg,
    char_u	**retarg)
{
    int		ret;
    char_u	*p;
    char_u	*expr_end;
    int		did_emsg_before = did_emsg;
    int		called_emsg_before = called_emsg;
    int		check_for_end = retarg == NULL;
    int		end_error = FALSE;

    p = skipwhite(arg);
    ret = eval1(&p, rettv, evalarg);

    if (ret != FAIL)
    {
	expr_end = p;
	p = skipwhite(p);

	// In Vim9 script a command block is not split at NL characters for
	// commands using an expression argument.  Skip over a '#' comment to
	// check for a following NL.  Require white space before the '#'.
	if (in_vim9script() && p > expr_end && retarg == NULL)
	    while (*p == '#')
	    {
		char_u *nl = vim_strchr(p, NL);

		if (nl == NULL)
		    break;
		p = skipwhite(nl + 1);
		if (eap != NULL && *p != NUL)
		    eap->nextcmd = p;
		check_for_end = FALSE;
	    }

	if (check_for_end)
	    end_error = !ends_excmd2(arg, p);
    }

    if (ret == FAIL || end_error)
    {
	if (ret != FAIL)
	    clear_tv(rettv);
	/*
	 * Report the invalid expression unless the expression evaluation has
	 * been cancelled due to an aborting error, an interrupt, or an
	 * exception, or we already gave a more specific error.
	 * Also check called_emsg for when using assert_fails().
	 */
	if (!aborting()
		&& did_emsg == did_emsg_before
		&& called_emsg == called_emsg_before
		&& (!in_vim9script() || !vim9_bad_comment(p)))
	{
	    if (end_error)
		semsg(_(e_trailing_characters_str), p);
	    else
		semsg(_(e_invalid_expression_str), arg);
	}

	if (eap != NULL && p != NULL)
	{
	    // Some of the expression may not have been consumed.
	    // Only execute a next command if it cannot be a "||" operator.
	    // The next command may be "catch".
	    char_u *nextcmd = check_nextcmd(p);
	    if (nextcmd != NULL && *nextcmd != '|')
		eap->nextcmd = nextcmd;
	}
	return FAIL;
    }

    if (retarg != NULL)
	*retarg = p;
    else if (check_for_end && eap != NULL)
	set_nextcmd(eap, p);

    return ret;
}

/*
 * Handle top level expression:
 *	expr2 ? expr1 : expr1
 *	expr2 ?? expr1
 *
 * "arg" must point to the first non-white of the expression.
 * "arg" is advanced to just after the recognized expression.
 *
 * Note: "rettv.v_lock" is not set.
 *
 * Return OK or FAIL.
 */
    int
eval1(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
{
    char_u  *p;
    int	    getnext;

    CLEAR_POINTER(rettv);

    /*
     * Get the first variable.
     */
    if (eval2(arg, rettv, evalarg) == FAIL)
	return FAIL;

    p = eval_next_non_blank(*arg, evalarg, &getnext);
    if (*p == '?')
    {
	int		op_falsy = p[1] == '?';
	int		result;
	typval_T	var2;
	evalarg_T	*evalarg_used = evalarg;
	evalarg_T	local_evalarg;
	int		orig_flags;
	int		evaluate;
	int		vim9script = in_vim9script();

	if (evalarg == NULL)
	{
	    init_evalarg(&local_evalarg);
	    evalarg_used = &local_evalarg;
	}
	orig_flags = evalarg_used->eval_flags;
	evaluate = evalarg_used->eval_flags & EVAL_EVALUATE;

	if (getnext)
	    *arg = eval_next_line(*arg, evalarg_used);
	else
	{
	    if (evaluate && vim9script && !VIM_ISWHITE(p[-1]))
	    {
		error_white_both(p, op_falsy ? 2 : 1);
		clear_tv(rettv);
		return FAIL;
	    }
	    *arg = p;
	}

	result = FALSE;
	if (evaluate)
	{
	    int		error = FALSE;

	    if (op_falsy)
		result = tv2bool(rettv);
	    else if (vim9script)
		result = tv_get_bool_chk(rettv, &error);
	    else if (tv_get_number_chk(rettv, &error) != 0)
		result = TRUE;
	    if (error || !op_falsy || !result)
		clear_tv(rettv);
	    if (error)
		return FAIL;
	}

	/*
	 * Get the second variable.  Recursive!
	 */
	if (op_falsy)
	    ++*arg;
	if (evaluate && vim9script && !IS_WHITE_OR_NUL((*arg)[1]))
	{
	    error_white_both(*arg - (op_falsy ? 1 : 0), op_falsy ? 2 : 1);
	    clear_tv(rettv);
	    return FAIL;
	}
	*arg = skipwhite_and_linebreak(*arg + 1, evalarg_used);
	evalarg_used->eval_flags = (op_falsy ? !result : result)
				  ? orig_flags : (orig_flags & ~EVAL_EVALUATE);
	if (eval1(arg, &var2, evalarg_used) == FAIL)
	{
	    evalarg_used->eval_flags = orig_flags;
	    return FAIL;
	}
	if (!op_falsy || !result)
	    *rettv = var2;

	if (!op_falsy)
	{
	    /*
	     * Check for the ":".
	     */
	    p = eval_next_non_blank(*arg, evalarg_used, &getnext);
	    if (*p != ':')
	    {
		emsg(_(e_missing_colon_after_questionmark));
		if (evaluate && result)
		    clear_tv(rettv);
		evalarg_used->eval_flags = orig_flags;
		return FAIL;
	    }
	    if (getnext)
		*arg = eval_next_line(*arg, evalarg_used);
	    else
	    {
		if (evaluate && vim9script && !VIM_ISWHITE(p[-1]))
		{
		    error_white_both(p, 1);
		    clear_tv(rettv);
		    evalarg_used->eval_flags = orig_flags;
		    return FAIL;
		}
		*arg = p;
	    }

	    /*
	     * Get the third variable.  Recursive!
	     */
	    if (evaluate && vim9script && !IS_WHITE_OR_NUL((*arg)[1]))
	    {
		error_white_both(*arg, 1);
		clear_tv(rettv);
		evalarg_used->eval_flags = orig_flags;
		return FAIL;
	    }
	    *arg = skipwhite_and_linebreak(*arg + 1, evalarg_used);
	    evalarg_used->eval_flags = !result ? orig_flags
					       : (orig_flags & ~EVAL_EVALUATE);
	    if (eval1(arg, &var2, evalarg_used) == FAIL)
	    {
		if (evaluate && result)
		    clear_tv(rettv);
		evalarg_used->eval_flags = orig_flags;
		return FAIL;
	    }
	    if (evaluate && !result)
		*rettv = var2;
	}

	if (evalarg == NULL)
	    clear_evalarg(&local_evalarg, NULL);
	else
	    evalarg->eval_flags = orig_flags;
    }

    return OK;
}

/*
 * Handle first level expression:
 *	expr2 || expr2 || expr2	    logical OR
 *
 * "arg" must point to the first non-white of the expression.
 * "arg" is advanced to just after the recognized expression.
 *
 * Return OK or FAIL.
 */
    static int
eval2(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
{
    char_u	*p;
    int		getnext;

    /*
     * Get the first expression.
     */
    if (eval3(arg, rettv, evalarg) == FAIL)
	return FAIL;

    /*
     * Handle the  "||" operator.
     */
    p = eval_next_non_blank(*arg, evalarg, &getnext);
    if (p[0] == '|' && p[1] == '|')
    {
	evalarg_T   *evalarg_used = evalarg;
	evalarg_T   local_evalarg;
	int	    evaluate;
	int	    orig_flags;
	long	    result = FALSE;
	typval_T    var2;
	int	    error = FALSE;
	int	    vim9script = in_vim9script();

	if (evalarg == NULL)
	{
	    init_evalarg(&local_evalarg);
	    evalarg_used = &local_evalarg;
	}
	orig_flags = evalarg_used->eval_flags;
	evaluate = orig_flags & EVAL_EVALUATE;
	if (evaluate)
	{
	    if (vim9script)
		result = tv_get_bool_chk(rettv, &error);
	    else if (tv_get_number_chk(rettv, &error) != 0)
		result = TRUE;
	    clear_tv(rettv);
	    if (error)
		return FAIL;
	}

	/*
	 * Repeat until there is no following "||".
	 */
	while (p[0] == '|' && p[1] == '|')
	{
	    if (getnext)
		*arg = eval_next_line(*arg, evalarg_used);
	    else
	    {
		if (evaluate && vim9script && !VIM_ISWHITE(p[-1]))
		{
		    error_white_both(p, 2);
		    clear_tv(rettv);
		    return FAIL;
		}
		*arg = p;
	    }

	    /*
	     * Get the second variable.
	     */
	    if (evaluate && vim9script && !IS_WHITE_OR_NUL((*arg)[2]))
	    {
		error_white_both(*arg, 2);
		clear_tv(rettv);
		return FAIL;
	    }
	    *arg = skipwhite_and_linebreak(*arg + 2, evalarg_used);
	    evalarg_used->eval_flags = !result ? orig_flags
					       : (orig_flags & ~EVAL_EVALUATE);
	    if (eval3(arg, &var2, evalarg_used) == FAIL)
		return FAIL;

	    /*
	     * Compute the result.
	     */
	    if (evaluate && !result)
	    {
		if (vim9script)
		    result = tv_get_bool_chk(&var2, &error);
		else if (tv_get_number_chk(&var2, &error) != 0)
		    result = TRUE;
		clear_tv(&var2);
		if (error)
		    return FAIL;
	    }
	    if (evaluate)
	    {
		if (vim9script)
		{
		    rettv->v_type = VAR_BOOL;
		    rettv->vval.v_number = result ? VVAL_TRUE : VVAL_FALSE;
		}
		else
		{
		    rettv->v_type = VAR_NUMBER;
		    rettv->vval.v_number = result;
		}
	    }

	    p = eval_next_non_blank(*arg, evalarg_used, &getnext);
	}

	if (evalarg == NULL)
	    clear_evalarg(&local_evalarg, NULL);
	else
	    evalarg->eval_flags = orig_flags;
    }

    return OK;
}

/*
 * Handle second level expression:
 *	expr3 && expr3 && expr3	    logical AND
 *
 * "arg" must point to the first non-white of the expression.
 * "arg" is advanced to just after the recognized expression.
 *
 * Return OK or FAIL.
 */
    static int
eval3(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
{
    char_u	*p;
    int		getnext;

    /*
     * Get the first expression.
     */
    if (eval4(arg, rettv, evalarg) == FAIL)
	return FAIL;

    /*
     * Handle the "&&" operator.
     */
    p = eval_next_non_blank(*arg, evalarg, &getnext);
    if (p[0] == '&' && p[1] == '&')
    {
	evalarg_T   *evalarg_used = evalarg;
	evalarg_T   local_evalarg;
	int	    orig_flags;
	int	    evaluate;
	long	    result = TRUE;
	typval_T    var2;
	int	    error = FALSE;
	int	    vim9script = in_vim9script();

	if (evalarg == NULL)
	{
	    init_evalarg(&local_evalarg);
	    evalarg_used = &local_evalarg;
	}
	orig_flags = evalarg_used->eval_flags;
	evaluate = orig_flags & EVAL_EVALUATE;
	if (evaluate)
	{
	    if (vim9script)
		result = tv_get_bool_chk(rettv, &error);
	    else if (tv_get_number_chk(rettv, &error) == 0)
		result = FALSE;
	    clear_tv(rettv);
	    if (error)
		return FAIL;
	}

	/*
	 * Repeat until there is no following "&&".
	 */
	while (p[0] == '&' && p[1] == '&')
	{
	    if (getnext)
		*arg = eval_next_line(*arg, evalarg_used);
	    else
	    {
		if (evaluate && vim9script && !VIM_ISWHITE(p[-1]))
		{
		    error_white_both(p, 2);
		    clear_tv(rettv);
		    return FAIL;
		}
		*arg = p;
	    }

	    /*
	     * Get the second variable.
	     */
	    if (evaluate && vim9script && !IS_WHITE_OR_NUL((*arg)[2]))
	    {
		error_white_both(*arg, 2);
		clear_tv(rettv);
		return FAIL;
	    }
	    *arg = skipwhite_and_linebreak(*arg + 2, evalarg_used);
	    evalarg_used->eval_flags = result ? orig_flags
					      : (orig_flags & ~EVAL_EVALUATE);
	    CLEAR_FIELD(var2);
	    if (eval4(arg, &var2, evalarg_used) == FAIL)
		return FAIL;

	    /*
	     * Compute the result.
	     */
	    if (evaluate && result)
	    {
		if (vim9script)
		    result = tv_get_bool_chk(&var2, &error);
		else if (tv_get_number_chk(&var2, &error) == 0)
		    result = FALSE;
		clear_tv(&var2);
		if (error)
		    return FAIL;
	    }
	    if (evaluate)
	    {
		if (vim9script)
		{
		    rettv->v_type = VAR_BOOL;
		    rettv->vval.v_number = result ? VVAL_TRUE : VVAL_FALSE;
		}
		else
		{
		    rettv->v_type = VAR_NUMBER;
		    rettv->vval.v_number = result;
		}
	    }

	    p = eval_next_non_blank(*arg, evalarg_used, &getnext);
	}

	if (evalarg == NULL)
	    clear_evalarg(&local_evalarg, NULL);
	else
	    evalarg->eval_flags = orig_flags;
    }

    return OK;
}

/*
 * Handle third level expression:
 *	var1 == var2
 *	var1 =~ var2
 *	var1 != var2
 *	var1 !~ var2
 *	var1 > var2
 *	var1 >= var2
 *	var1 < var2
 *	var1 <= var2
 *	var1 is var2
 *	var1 isnot var2
 *
 * "arg" must point to the first non-white of the expression.
 * "arg" is advanced to just after the recognized expression.
 *
 * Return OK or FAIL.
 */
    static int
eval4(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
{
    char_u	*p;
    int		getnext;
    exprtype_T	type = EXPR_UNKNOWN;
    int		len = 2;
    int		type_is = FALSE;

    /*
     * Get the first expression.
     */
    if (eval5(arg, rettv, evalarg) == FAIL)
	return FAIL;

    p = eval_next_non_blank(*arg, evalarg, &getnext);

    type = get_compare_type(p, &len, &type_is);

    /*
     * If there is a comparative operator, use it.
     */
    if (type != EXPR_UNKNOWN)
    {
	typval_T    var2;
	int	    ic;
	int	    vim9script = in_vim9script();
	int	    evaluate = evalarg == NULL
				   ? 0 : (evalarg->eval_flags & EVAL_EVALUATE);
	long	    comp_lnum = SOURCING_LNUM;

	if (getnext)
	{
	    *arg = eval_next_line(*arg, evalarg);
	    p = *arg;
	}
	else if (evaluate && vim9script && !VIM_ISWHITE(**arg))
	{
	    error_white_both(*arg, len);
	    clear_tv(rettv);
	    return FAIL;
	}

	if (vim9script && type_is && (p[len] == '?' || p[len] == '#'))
	{
	    semsg(_(e_invalid_expression_str), p);
	    clear_tv(rettv);
	    return FAIL;
	}

	// extra question mark appended: ignore case
	if (p[len] == '?')
	{
	    ic = TRUE;
	    ++len;
	}
	// extra '#' appended: match case
	else if (p[len] == '#')
	{
	    ic = FALSE;
	    ++len;
	}
	// nothing appended: use 'ignorecase' if not in Vim script
	else
	    ic = vim9script ? FALSE : p_ic;

	/*
	 * Get the second variable.
	 */
	if (evaluate && vim9script && !IS_WHITE_OR_NUL(p[len]))
	{
	    error_white_both(p, len);
	    clear_tv(rettv);
	    return FAIL;
	}
	*arg = skipwhite_and_linebreak(p + len, evalarg);
	if (eval5(arg, &var2, evalarg) == FAIL)
	{
	    clear_tv(rettv);
	    return FAIL;
	}
	if (evaluate)
	{
	    int ret;

	    // use the line of the comparison for messages
	    SOURCING_LNUM = comp_lnum;
	    if (vim9script && check_compare_types(type, rettv, &var2) == FAIL)
	    {
		ret = FAIL;
		clear_tv(rettv);
	    }
	    else
		ret = typval_compare(rettv, &var2, type, ic);
	    clear_tv(&var2);
	    return ret;
	}
    }

    return OK;
}

/*
 * Make a copy of blob "tv1" and append blob "tv2".
 */
    void
eval_addblob(typval_T *tv1, typval_T *tv2)
{
    blob_T  *b1 = tv1->vval.v_blob;
    blob_T  *b2 = tv2->vval.v_blob;
    blob_T  *b = blob_alloc();
    int	    i;

    if (b == NULL)
	return;

    for (i = 0; i < blob_len(b1); i++)
	ga_append(&b->bv_ga, blob_get(b1, i));
    for (i = 0; i < blob_len(b2); i++)
	ga_append(&b->bv_ga, blob_get(b2, i));

    clear_tv(tv1);
    rettv_blob_set(tv1, b);
}

/*
 * Make a copy of list "tv1" and append list "tv2".
 */
    int
eval_addlist(typval_T *tv1, typval_T *tv2)
{
    typval_T var3;

    // concatenate Lists
    if (list_concat(tv1->vval.v_list, tv2->vval.v_list, &var3) == FAIL)
    {
	clear_tv(tv1);
	clear_tv(tv2);
	return FAIL;
    }
    clear_tv(tv1);
    *tv1 = var3;
    return OK;
}

/*
 * Handle the bitwise left/right shift operator expression:
 *	var1 << var2
 *	var1 >> var2
 *
 * "arg" must point to the first non-white of the expression.
 * "arg" is advanced to just after the recognized expression.
 *
 * Return OK or FAIL.
 */
    static int
eval5(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
{
    /*
     * Get the first expression.
     */
    if (eval6(arg, rettv, evalarg) == FAIL)
	return FAIL;

    /*
     * Repeat computing, until no '<<' or '>>' is following.
     */
    for (;;)
    {
	char_u		*p;
	int		getnext;
	exprtype_T	type;
	int		evaluate;
	typval_T	var2;
	int		vim9script;

	p = eval_next_non_blank(*arg, evalarg, &getnext);
	if (p[0] == '<' && p[1] == '<')
	    type = EXPR_LSHIFT;
	else if (p[0] == '>' && p[1] == '>')
	    type = EXPR_RSHIFT;
	else
	    return OK;

	// Handle a bitwise left or right shift operator
	evaluate = evalarg == NULL ? 0 : (evalarg->eval_flags & EVAL_EVALUATE);
	if (evaluate && rettv->v_type != VAR_NUMBER)
	{
	    // left operand should be a number
	    emsg(_(e_bitshift_ops_must_be_number));
	    clear_tv(rettv);
	    return FAIL;
	}

	vim9script = in_vim9script();
	if (getnext)
	{
	    *arg = eval_next_line(*arg, evalarg);
	    p = *arg;
	}
	else if (evaluate && vim9script && !VIM_ISWHITE(**arg))
	{
	    error_white_both(*arg, 2);
	    clear_tv(rettv);
	    return FAIL;
	}

	/*
	 * Get the second variable.
	 */
	if (evaluate && vim9script && !IS_WHITE_OR_NUL(p[2]))
	{
	    error_white_both(p, 2);
	    clear_tv(rettv);
	    return FAIL;
	}
	*arg = skipwhite_and_linebreak(p + 2, evalarg);
	if (eval6(arg, &var2, evalarg) == FAIL)
	{
	    clear_tv(rettv);
	    return FAIL;
	}

	if (evaluate)
	{
	    if (var2.v_type != VAR_NUMBER || var2.vval.v_number < 0)
	    {
		// right operand should be a positive number
		if (var2.v_type != VAR_NUMBER)
		    emsg(_(e_bitshift_ops_must_be_number));
		else
		    emsg(_(e_bitshift_ops_must_be_positive));
		clear_tv(rettv);
		clear_tv(&var2);
		return FAIL;
	    }

	    if (var2.vval.v_number > MAX_LSHIFT_BITS)
		// shifting more bits than we have always results in zero
		rettv->vval.v_number = 0;
	    else if (type == EXPR_LSHIFT)
		rettv->vval.v_number =
		      (uvarnumber_T)rettv->vval.v_number << var2.vval.v_number;
	    else
		rettv->vval.v_number =
		      (uvarnumber_T)rettv->vval.v_number >> var2.vval.v_number;
	}

	clear_tv(&var2);
    }

    return OK;
}

/*
 * Handle fifth level expression:
 *	+	number addition, concatenation of list or blob
 *	-	number subtraction
 *	.	string concatenation (if script version is 1)
 *	..	string concatenation
 *
 * "arg" must point to the first non-white of the expression.
 * "arg" is advanced to just after the recognized expression.
 *
 * Return OK or FAIL.
 */
    static int
eval6(char_u **arg, typval_T *rettv, evalarg_T *evalarg)
{
    /*
     * Get the first expression.
     */
    if (eval7(arg, rettv, evalarg, FALSE) == FAIL)
	return FAIL;

    /*
     * Repeat computing, until no '+', '-' or '.' is following.
     */
    for (;;)
    {
	int	    evaluate;
	int	    getnext;
	char_u	    *p;
	int	    op;
	int	    oplen;
	int	    concat;
	typval_T    var2;
	int	    vim9script = in_vim9script();

	// "." is only string concatenation when scriptversion is 1
	// "+=", "-=" and "..=" are assignments
	// "++" and "--" on the next line are a separate command.
	p = eval_next_non_blank(*arg, evalarg, &getnext);
	op = *p;
	concat = op == '.' && (*(p + 1) == '.' || in_old_script(2));
	if ((op != '+' && op != '-' && !concat) || p[1] == '='
					       || (p[1] == '.' && p[2] == '='))
	    break;
	if (getnext && (op == '+' || op == '-') && p[0] == p[1])
	    break;

	evaluate = evalarg == NULL ? 0 : (evalarg->eval_flags & EVAL_EVALUATE);
	oplen = (concat && p[1] == '.') ? 2 : 1;
	if (getnext)
	    *arg = eval_next_line(*arg, evalarg);
	else
	{
	    if (evaluate && vim9script && !VIM_ISWHITE(**arg))
	    {
		error_white_both(*arg, oplen);
		clear_tv(rettv);
		return FAIL;
	    }
	    *arg = p;
	}
	if ((op != '+' || (rettv->v_type != VAR_LIST
						 && rettv->v_type != VAR_BLOB))
		&& (op == '.' || rettv->v_type != VAR_FLOAT)
		&& evaluate)
	{
	    int		error = FALSE;

	    // For "list + ...", an illegal use of the first operand as
	    // a number cannot be determined before evaluating the 2nd
	    // operand: if this is also a list, all is ok.
	    // For "something . ...", "something - ..." or "non-list + ...",
	    // we know that the first operand needs to be a string or number
	    // without evaluating the 2nd operand.  So check before to avoid
	    // side effects after an error.
	    if (op != '.')
		tv_get_number_chk(rettv, &error);
	    if ((op == '.' && tv_get_string_chk(rettv) == NULL) || error)
	    {
		clear_tv(rettv);
		return FAIL;
	    }
	}

	/*
	 * Get the second variable.
	 */
	if (evaluate && vim9script && !IS_WHITE_OR_NUL((*arg)[oplen]))
	{
	    error_white_both(*arg, oplen);
	    clear_tv(rettv);
	    return FAIL;
	}
	*arg = skipwhite_and_linebreak(*arg + oplen, evalarg);
	if (eval7(arg, &var2, evalarg, !vim9script && op == '.') == FAIL)
	{
	    clear_tv(rettv);
	    return FAIL;
	}

	if (evaluate)
	{
	    /*
	     * Compute the result.
	     */
	    if (op == '.')
	    {
		char_u	buf1[NUMBUFLEN], buf2[NUMBUFLEN];
		char_u	*s1 = tv_get_string_buf(rettv, buf1);
		char_u	*s2 = NULL;

		if (vim9script && (var2.v_type == VAR_VOID
			|| var2.v_type == VAR_CHANNEL
			|| var2.v_type == VAR_JOB))
		    semsg(_(e_using_invalid_value_as_string_str),
						   vartype_name(var2.v_type));
		else if (vim9script && var2.v_type == VAR_FLOAT)
		{
		    vim_snprintf((char *)buf2, NUMBUFLEN, "%g",
							    var2.vval.v_float);
		    s2 = buf2;
		}
		else
		    s2 = tv_get_string_buf_chk(&var2, buf2);
		if (s2 == NULL)		// type error ?
		{
		    clear_tv(rettv);
		    clear_tv(&var2);
		    return FAIL;
		}
		p = concat_str(s1, s2);
		clear_tv(rettv);
		rettv->v_type = VAR_STRING;
		rettv->vval.v_string = p;
	    }
	    else if (op == '+' && rettv->v_type == VAR_BLOB
						   && var2.v_type == VAR_BLOB)
		eval_addblob(rettv, &var2);
	    else if (op == '+' && rettv->v_type == VAR_LIST
						   && var2.v_type == VAR_LIST)
	    {
		if (eval_addlist(rettv, &var2) == FAIL)
		    return FAIL;
	    }
	    else
	    {
		int		error = FALSE;
		varnumber_T	n1, n2;
		float_T		f1 = 0, f2 = 0;

		if (rettv->v_type == VAR_FLOAT)
		{
		    f1 = rettv->vval.v_float;
		    n1 = 0;
		}
		else
		{
		    n1 = tv_get_number_chk(rettv, &error);
		    if (error)
		    {
			// This can only happen for "list + non-list" or
			// "blob + non-blob".  For "non-list + ..." or
			// "something - ...", we returned before evaluating the
			// 2nd operand.
			clear_tv(rettv);
			clear_tv(&var2);
			return FAIL;
		    }
		    if (var2.v_type == VAR_FLOAT)
			f1 = n1;
		}
		if (var2.v_type == VAR_FLOAT)
		{
		    f2 = var2.vval.v_float;
		    n2 = 0;
		}
		else
		{
		    n2 = tv_get_number_chk(&var2, &error);
		    if (error)
		    {
			clear_tv(rettv);
			clear_tv(&var2);
			return FAIL;
		    }
		    if (rettv->v_type == VAR_FLOAT)
			f2 = n2;
		}
		clear_tv(rettv);

		// If there is a float on either side the result is a float.
		if (rettv->v_type == VAR_FLOAT || var2.v_type == VAR_FLOAT)
		{
		    if (op == '+')
			f1 = f1 + f2;
		    else
			f1 = f1 - f2;
		    rettv->v_type = VAR_FLOAT;
		    rettv->vval.v_float = f1;
		}
		else
		{
		    if (op == '+')
			n1 = n1 + n2;
		    else
			n1 = n1 - n2;
		    rettv->v_type = VAR_NUMBER;
		    rettv->vval.v_number = n1;
		}
	    }
	    clear_tv(&var2);
	}
    }
    return OK;
}

/*
 * Handle sixth level expression:
 *	*	number multiplication
 *	/	number division
 *	%	number modulo
 *
 * "arg" must point to the first non-white of the expression.
 * "arg" is advanced to just after the recognized expression.
 *
 * Return OK or FAIL.
 */
    static int
eval7(
    char_u	**arg,
    typval_T	*rettv,
    evalarg_T	*evalarg,
    int		want_string)  // after "." operator
{
    int	    use_float = FALSE;

    /*
     * Get the first expression.
     */
    if (eval8(arg, rettv, evalarg, want_string) == FAIL)
	return FAIL;

    /*
     * Repeat computing, until no '*', '/' or '%' is following.
     */
    for (;;)
    {
	int	    evaluate;
	int	    getnext;
	typval_T    var2;
	char_u	    *p;
	int	    op;
	varnumber_T n1, n2;
	float_T	    f1, f2;
	int	    error;

	// "*=", "/=" and "%=" are assignments
	p = eval_next_non_blank(*arg, evalarg, &getnext);
	op = *p;
	if ((op != '*' && op != '/' && op != '%') || p[1] == '=')
	    break;

	evaluate = evalarg == NULL ? 0 : (evalarg->eval_flags & EVAL_EVALUATE);
	if (getnext)
	    *arg = eval_next_line(*arg, evalarg);
	else
	{
	    if (evaluate && in_vim9script() && !VIM_ISWHITE(**arg))
	    {
		error_white_both(*arg, 1);
		clear_tv(rettv);
		return FAIL;
	    }
	    *arg = p;
	}

	f1 = 0;
	f2 = 0;
	error = FALSE;
	if (evaluate)
	{
	    if (rettv->v_type == VAR_FLOAT)
	    {
		f1 = rettv->vval.v_float;
		use_float = TRUE;
		n1 = 0;
	    }
	    else
		n1 = tv_get_number_chk(rettv, &error);
	    clear_tv(rettv);
	    if (error)
		return FAIL;
	}
	else
	    n1 = 0;

	/*
	 * Get the second variable.
	 */
	if (evaluate && in_vim9script() && !IS_WHITE_OR_NUL((*arg)[1]))
	{
	    error_white_both(*arg, 1);
	    clear_tv(rettv);
	    return FAIL;
	}
	*arg = skipwhite_and_linebreak(*arg + 1, evalarg);
	if (eval8(arg, &var2, evalarg, FALSE) == FAIL)
	    return FAIL;

	if (evaluate)
	{
	    if (var2.v_type == VAR_FLOAT)
	    {
		if (!use_float)
		{
		    f1 = n1;
		    use_float = TRUE;
		}
		f2 = var2.vval.v_float;
		n2 = 0;
	    }
	    else
	    {
		n2 = tv_get_number_chk(&var2, &error);
		clear_tv(&var2);
		if (error)
		    return FAIL;
		if (use_float)
		    f2 = n2;
	    }

	    /*
	     * Compute the result.
	     * When either side is a float the result is a float.
	     */
	    if (use_float)
	    {
		if (op == '*')
		    f1 = f1 * f2;
		else if (op == '/')
		{
#ifdef VMS
		    // VMS crashes on divide by zero, work around it
		    if (f2 == 0.0)
		    {
			if (f1 == 0)
			    f1 = -1 * __F_FLT_MAX - 1L;   // similar to NaN
			else if (f1 < 0)
			    f1 = -1 * __F_FLT_MAX;
			else
			    f1 = __F_FLT_MAX;
		    }
		    else
			f1 = f1 / f2;
#else
		    // We rely on the floating point library to handle divide
		    // by zero to result in "inf" and not a crash.
		    f1 = f1 / f2;
#endif
		}
		else
		{
		    emsg(_(e_cannot_use_percent_with_float));
		    return FAIL;
		}
		rettv->v_type = VAR_FLOAT;
		rettv->vval.v_float = f1;
	    }
	    else
	    {
		int	    failed = FALSE;

		if (op == '*')
		    n1 = n1 * n2;
		else if (op == '/')
		    n1 = num_divide(n1, n2, &failed);
		else
		    n1 = num_modulus(n1, n2, &failed);
		if (failed)
		    return FAIL;

		rettv->v_type = VAR_NUMBER;
		rettv->vval.v_number = n1;
	    }
	}
    }

    return OK;
}

/*
 * Handle a type cast before a base level expression.
 * "arg" must point to the first non-white of the expression.
 * "arg" is advanced to just after the recognized expression.
 * Return OK or FAIL.
 */
    static int
eval8(
    char_u	**arg,
    typval_T	*rettv,
    evalarg_T	*evalarg,
    int		want_string)	// after "." operator
{
    type_T	*want_type = NULL;
    garray_T	type_list;	    // list of pointers to allocated types
    int		res;
    int		evaluate = evalarg == NULL ? 0
				       : (evalarg->eval_flags & EVAL_EVALUATE);

    // Recognize <type> in Vim9 script only.
    if (in_vim9script() && **arg == '<' && eval_isnamec1((*arg)[1])
					     && STRNCMP(*arg, "<SNR>", 5) != 0)
    {
	++*arg;
	ga_init2(&type_list, sizeof(type_T *), 10);
	want_type = parse_type(arg, &type_list, TRUE);
	if (want_type == NULL && (evaluate || **arg != '>'))
	{
	    clear_type_list(&type_list);
	    return FAIL;
	}

	if (**arg != '>')
	{
	    if (*skipwhite(*arg) == '>')
		semsg(_(e_no_white_space_allowed_before_str_str), ">", *arg);
	    else
		emsg(_(e_missing_gt));
	    clear_type_list(&type_list);
	    return FAIL;
	}
	++*arg;
	*arg = skipwhite_and_linebreak(*arg, evalarg);
    }

    res = eval9(arg, rettv, evalarg, want_string);

    if (want_type != NULL && evaluate)
    {
	if (res == OK)
	{
	    type_T *actual = typval2type(rettv, get_copyID(), &type_list,
							       TVTT_DO_MEMBER);

	    if (!equal_type(want_type, actual, 0))
	    {
		if (want_type == &t_bool && actual != &t_bool
					&& (actual->tt_flags & TTFLAG_BOOL_OK))
		{
		    int n = tv2bool(rettv);

		    // can use "0" and "1" for boolean in some places
		    clear_tv(rettv);
		    rettv->v_type = VAR_BOOL;
		    rettv->vval.v_number = n ? VVAL_TRUE : VVAL_FALSE;
		}
		else
		{
		    where_T where = WHERE_INIT;

		    res = check_type(want_type, actual, TRUE, where);
		}
	    }
	}
	clear_type_list(&type_list);
    }

    return res;
}

    int
eval_leader(char_u **arg, int vim9)
{
    char_u	*s = *arg;
    char_u	*p = *arg;

    while (*p == '!' || *p == '-' || *p == '+')
    {
	char_u *n = skipwhite(p + 1);

	// ++, --, -+ and +- are not accepted in Vim9 script
	if (vim9 && (*p == '-' || *p == '+') && (*n == '-' || *n == '+'))
	{
	    semsg(_(e_invalid_expression_str), s);
	    return FAIL;
	}
	p = n;
    }
    *arg = p;
    return OK;
}

/*
 * Check for a predefined value "true", "false" and "null.*".
 * Return OK when recognized.
 */
    int
handle_predefined(char_u *s, int len, typval_T *rettv)
{
    switch (len)
    {
	case 4: if (STRNCMP(s, "true", 4) == 0)
		{
		    rettv->v_type = VAR_BOOL;
		    rettv->vval.v_number = VVAL_TRUE;
		    return OK;
		}
		if (STRNCMP(s, "null", 4) == 0)
		{
		    rettv->v_type = VAR_SPECIAL;
		    rettv->vval.v_number = VVAL_NULL;
		    return OK;
		}
		break;
	case 5: if (STRNCMP(s, "false", 5) == 0)
		{
		    rettv->v_type = VAR_BOOL;
		    rettv->vval.v_number = VVAL_FALSE;
		    return OK;
		}
		break;
	case 8: if (STRNCMP(s, "null_job", 8) == 0)
		{
#ifdef FEAT_JOB_CHANNEL
		    rettv->v_type = VAR_JOB;
		    rettv->vval.v_job = NULL;
#else
		    rettv->v_type = VAR_SPECIAL;
		    rettv->vval.v_number = VVAL_NULL;
#endif
		    return OK;
		}
		break;
	case 9:
		if (STRNCMP(s, "null_", 5) != 0)
		    break;
		if (STRNCMP(s + 5, "list", 4) == 0)
		{
		    rettv->v_type = VAR_LIST;
		    rettv->vval.v_list = NULL;
		    return OK;
		}
		if (STRNCMP(s + 5, "dict", 4) == 0)
		{
		    rettv->v_type = VAR_DICT;
		    rettv->vval.v_dict = NULL;
		    return OK;
		}
		if (STRNCMP(s + 5, "blob", 4) == 0)
		{
		    rettv->v_type = VAR_BLOB;
		    rettv->vval.v_blob = NULL;
		    return OK;
		}
		break;
	case 10: if (STRNCMP(s, "null_class", 10) == 0)
		{
		    rettv->v_type = VAR_CLASS;
		    rettv->vval.v_class = NULL;
		    return OK;
		}
		 break;
	case 11: if (STRNCMP(s, "null_string", 11) == 0)
		{
		    rettv->v_type = VAR_STRING;
		    rettv->vval.v_string = NULL;
		    return OK;
		}
		if (STRNCMP(s, "null_object", 11) == 0)
		{
		    rettv->v_type = VAR_OBJECT;
		    rettv->vval.v_object = NULL;
		    return OK;
		}
		break;
	case 12:
		if (STRNCMP(s, "null_channel", 12) == 0)
		{
#ifdef FEAT_JOB_CHANNEL
		    rettv->v_type = VAR_CHANNEL;
		    rettv->vval.v_channel = NULL;
#else
		    rettv->v_type = VAR_SPECIAL;
		    rettv->vval.v_number = VVAL_NULL;
#endif
		    return OK;
		}
		if (STRNCMP(s, "null_partial", 12) == 0)
		{
		    rettv->v_type = VAR_PARTIAL;
		    rettv->vval.v_partial = NULL;
		    return OK;
		}
		break;
	case 13: if (STRNCMP(s, "null_function", 13) == 0)
		{
		    rettv->v_type = VAR_FUNC;
		    rettv->vval.v_string = NULL;
		    return OK;
		}
		break;
    }
    return FAIL;
}

/*
 * Handle sixth level expression:
 *  number		number constant
 *  0zFFFFFFFF		Blob constant
 *  "string"		string constant
 *  'string'		literal string constant
 *  &option-name	option value
 *  @r			register contents
 *  identifier		variable value
 *  function()		function call
 *  $VAR		environment variable
 *  (expression)	nested expression
 *  [expr, expr]	List
 *  {arg, arg -> expr}	Lambda
 *  {key: val, key: val}   Dictionary
 *  #{key: val, key: val}  Dictionary with literal keys
 *
 *  Also handle:
 *  ! in front		logical NOT
 *  - in front		unary minus
 *  + in front		unary plus (ignored)
 *  trailing []		subscript in String or List
 *  trailing .name	entry in Dictionary
 *  trailing ->name()	method call
 *
 * "arg" must point to the first non-white of the expression.
 * "arg" is advanced to just after the recognized expression.
 *
 * Return OK or FAIL.
 */
    static int
eval9(
    char_u	**arg,
    typval_T	*rettv,
    evalarg_T	*evalarg,
    int		want_string)	// after "." operator
{
    int		evaluate = evalarg != NULL
				      && (evalarg->eval_flags & EVAL_EVALUATE);
    int		len;
    char_u	*s;
    char_u	*name_start = NULL;
    char_u	*start_leader, *end_leader;
    int		ret = OK;
    char_u	*alias;
    static int	recurse = 0;
    int		vim9script = in_vim9script();

    /*
     * Initialise variable so that clear_tv() can't mistake this for a
     * string and free a string that isn't there.
     */
    rettv->v_type = VAR_UNKNOWN;

    /*
     * Skip '!', '-' and '+' characters.  They are handled later.
     */
    start_leader = *arg;
    if (eval_leader(arg, vim9script) == FAIL)
	return FAIL;
    end_leader = *arg;

    if (**arg == '.' && (!isdigit(*(*arg + 1)) || in_old_script(2)))
    {
	semsg(_(e_invalid_expression_str), *arg);
	++*arg;
	return FAIL;
    }

    // Limit recursion to 1000 levels.  At least at 10000 we run out of stack
    // and crash.  With MSVC the stack is smaller.
    if (recurse ==
#ifdef _MSC_VER
		    300
#else
		    1000
#endif
		    )
    {
	semsg(_(e_expression_too_recursive_str), *arg);
	return FAIL;
    }
    ++recurse;

    switch (**arg)
    {
    /*
     * Number constant.
     */
    case '0':
    case '1':
    case '2':
    case '3':
    case '4':
    case '5':
    case '6':
    case '7':
    case '8':
    case '9':
    case '.':	ret = eval_number(arg, rettv, evaluate, want_string);

		// Apply prefixed "-" and "+" now.  Matters especially when
		// "->" follows.
		if (ret == OK && evaluate && end_leader > start_leader
						  && rettv->v_type != VAR_BLOB)
		    ret = eval9_leader(rettv, TRUE, start_leader, &end_leader);
		break;

    /*
     * String constant: "string".
     */
    case '"':	ret = eval_string(arg, rettv, evaluate, FALSE);
		break;

    /*
     * Literal string constant: 'str''ing'.
     */
    case '\'':	ret = eval_lit_string(arg, rettv, evaluate, FALSE);
		break;

    /*
     * List: [expr, expr]
     */
    case '[':	ret = eval_list(arg, rettv, evalarg, TRUE);
		break;

    /*
     * Dictionary: #{key: val, key: val}
     */
    case '#':	if (vim9script)
		{
		    ret = vim9_bad_comment(*arg) ? FAIL : NOTDONE;
		}
		else if ((*arg)[1] == '{')
		{
		    ++*arg;
		    ret = eval_dict(arg, rettv, evalarg, TRUE);
		}
		else
		    ret = NOTDONE;
		break;

    /*
     * Lambda: {arg, arg -> expr}
     * Dictionary: {'key': val, 'key': val}
     */
    case '{':	if (vim9script)
		    ret = NOTDONE;
		else
		    ret = get_lambda_tv(arg, rettv, vim9script, evalarg);
		if (ret == NOTDONE)
		    ret = eval_dict(arg, rettv, evalarg, FALSE);
		break;

    /*
     * Option value: &name
     */
    case '&':	ret = eval_option(arg, rettv, evaluate);
		break;

    /*
     * Environment variable: $VAR.
     * Interpolated string: $"string" or $'string'.
     */
    case '$':	if ((*arg)[1] == '"' || (*arg)[1] == '\'')
		    ret = eval_interp_string(arg, rettv, evaluate);
		else
		    ret = eval_env_var(arg, rettv, evaluate);
		break;

    /*
     * Register contents: @r.
     */
    case '@':	++*arg;
		if (evaluate)
		{
		    if (vim9script && IS_WHITE_OR_NUL(**arg))
			semsg(_(e_syntax_error_at_str), *arg);
		    else if (vim9script && !valid_yank_reg(**arg, FALSE))
			emsg_invreg(**arg);
		    else
		    {
			rettv->v_type = VAR_STRING;
			rettv->vval.v_string = get_reg_contents(**arg,
								GREG_EXPR_SRC);
		    }
		}
		if (**arg != NUL)
		    ++*arg;
		break;

    /*
     * nested expression: (expression).
     * or lambda: (arg) => expr
     */
    case '(':	ret = NOTDONE;
		if (vim9script)
		{
		    ret = get_lambda_tv(arg, rettv, TRUE, evalarg);
		    if (ret == OK && evaluate)
		    {
			ufunc_T *ufunc = rettv->vval.v_partial->pt_func;

			// Compile it here to get the return type.  The return
			// type is optional, when it's missing use t_unknown.
			// This is recognized in compile_return().
			if (ufunc->uf_ret_type->tt_type == VAR_VOID)
			    ufunc->uf_ret_type = &t_unknown;
			if (compile_def_function(ufunc, FALSE,
					get_compile_type(ufunc), NULL) == FAIL)
			{
			    clear_tv(rettv);
			    ret = FAIL;
			}
		    }
		}
		if (ret == NOTDONE)
		{
		    *arg = skipwhite_and_linebreak(*arg + 1, evalarg);
		    ret = eval1(arg, rettv, evalarg);	// recursive!

		    *arg = skipwhite_and_linebreak(*arg, evalarg);
		    if (**arg == ')')
			++*arg;
		    else if (ret == OK)
		    {
			emsg(_(e_missing_closing_paren));
			clear_tv(rettv);
			ret = FAIL;
		    }
		}
		break;

    default:	ret = NOTDONE;
		break;
    }

    if (ret == NOTDONE)
    {
	/*
	 * Must be a variable or function name.
	 * Can also be a curly-braces kind of name: {expr}.
	 */
	s = *arg;
	len = get_name_len(arg, &alias, evaluate, TRUE);
	if (alias != NULL)
	    s = alias;

	if (len <= 0)
	    ret = FAIL;
	else
	{
	    int	    flags = evalarg == NULL ? 0 : evalarg->eval_flags;

	    if (evaluate && vim9script && len == 1 && *s == '_')
	    {
		emsg(_(e_cannot_use_underscore_here));
		ret = FAIL;
	    }
	    else if (evaluate && vim9script && len > 2
						 && s[0] == 's' && s[1] == ':')
	    {
		semsg(_(e_cannot_use_s_colon_in_vim9_script_str), s);
		ret = FAIL;
	    }
	    else if ((vim9script ? **arg : *skipwhite(*arg)) == '(')
	    {
		// "name(..."  recursive!
		*arg = skipwhite(*arg);
		ret = eval_func(arg, evalarg, s, len, rettv, flags, NULL);
	    }
	    else if (evaluate)
	    {
		// get the value of "true", "false", etc. or a variable
		ret = FAIL;
		if (vim9script)
		    ret = handle_predefined(s, len, rettv);
		if (ret == FAIL)
		{
		    name_start = s;
		    ret = eval_variable(s, len, 0, rettv, NULL,
					   EVAL_VAR_VERBOSE + EVAL_VAR_IMPORT);
		}
	    }
	    else
	    {
		// skip the name
		check_vars(s, len);
		ret = OK;
	    }
	}
	vim_free(alias);
    }

    // Handle following '[', '(' and '.' for expr[expr], expr.name,
    // expr(expr), expr->name(expr)
    if (ret == OK)
	ret = handle_subscript(arg, name_start, rettv, evalarg, evaluate);

    /*
     * Apply logical NOT and unary '-', from right to left, ignore '+'.
     */
    if (ret == OK && evaluate && end_leader > start_leader)
	ret = eval9_leader(rettv, FALSE, start_leader, &end_leader);

    --recurse;
    return ret;
}

/*
 * Apply the leading "!" and "-" before an eval9 expression to "rettv".
 * When "numeric_only" is TRUE only handle "+" and "-".
 * Adjusts "end_leaderp" until it is at "start_leader".
 */
    static int
eval9_leader(
	typval_T    *rettv,
	int	    numeric_only,
	char_u	    *start_leader,
	char_u	    **end_leaderp)
{
    char_u	*end_leader = *end_leaderp;
    int		ret = OK;
    int		error = FALSE;
    varnumber_T val = 0;
    vartype_T	type = rettv->v_type;
    int		vim9script = in_vim9script();
    float_T	    f = 0.0;

    if (rettv->v_type == VAR_FLOAT)
	f = rettv->vval.v_float;
    else
    {
	while (VIM_ISWHITE(end_leader[-1]))
	    --end_leader;
	if (vim9script && end_leader[-1] == '!')
	    val = tv2bool(rettv);
	else
	    val = tv_get_number_chk(rettv, &error);
    }
    if (error)
    {
	clear_tv(rettv);
	ret = FAIL;
    }
    else
    {
	while (end_leader > start_leader)
	{
	    --end_leader;
	    if (*end_leader == '!')
	    {
		if (numeric_only)
		{
		    ++end_leader;
		    break;
		}
		if (rettv->v_type == VAR_FLOAT)
		{
		    if (vim9script)
		    {
			rettv->v_type = VAR_BOOL;
			val = f == 0.0 ? VVAL_TRUE : VVAL_FALSE;
		    }
		    else
			f = !f;
		}
		else
		{
		    val = !val;
		    type = VAR_BOOL;
		}
	    }
	    else if (*end_leader == '-')
	    {
		if (rettv->v_type == VAR_FLOAT)
		    f = -f;
		else
		{
		    val = -val;
		    type = VAR_NUMBER;
		}
	    }
	}
	if (rettv->v_type == VAR_FLOAT)
	{
	    clear_tv(rettv);
	    rettv->vval.v_float = f;
	}
	else
	{
	    clear_tv(rettv);
	    if (vim9script)
		rettv->v_type = type;
	    else
		rettv->v_type = VAR_NUMBER;
	    rettv->vval.v_number = val;
	}
    }
    *end_leaderp = end_leader;
    return ret;
}

/*
 * Call the function referred to in "rettv".
 */
    static int
call_func_rettv(
	char_u	    **arg,
	evalarg_T   *evalarg,
	typval_T    *rettv,
	int	    evaluate,
	dict_T	    *selfdict,
	typval_T    *basetv)
{
    partial_T	*pt = NULL;
    funcexe_T	funcexe;
    typval_T	functv;
    char_u	*s;
    int		ret;

    // need to copy the funcref so that we can clear rettv
    if (evaluate)
    {
	functv = *rettv;
	rettv->v_type = VAR_UNKNOWN;

	// Invoke the function.  Recursive!
	if (functv.v_type == VAR_PARTIAL)
	{
	    pt = functv.vval.v_partial;
	    s = partial_name(pt);
	}
	else
	{
	    s = functv.vval.v_string;
	    if (s == NULL || *s == NUL)
	    {
		emsg(_(e_empty_function_name));
		ret = FAIL;
		goto theend;
	    }
	}
    }
    else
	s = (char_u *)"";

    CLEAR_FIELD(funcexe);
    funcexe.fe_firstline = curwin->w_cursor.lnum;
    funcexe.fe_lastline = curwin->w_cursor.lnum;
    funcexe.fe_evaluate = evaluate;
    funcexe.fe_partial = pt;
    funcexe.fe_selfdict = selfdict;
    funcexe.fe_basetv = basetv;
    ret = get_func_tv(s, -1, rettv, arg, evalarg, &funcexe);

theend:
    // Clear the funcref afterwards, so that deleting it while
    // evaluating the arguments is possible (see test55).
    if (evaluate)
	clear_tv(&functv);

    return ret;
}

/*
 * Evaluate "->method()".
 * "*arg" points to "method".
 * Returns FAIL or OK. "*arg" is advanced to after the ')'.
 */
    static int
eval_lambda(
    char_u	**arg,
    typval_T	*rettv,
    evalarg_T	*evalarg,
    int		verbose)	// give error messages
{
    int		evaluate = evalarg != NULL
				      && (evalarg->eval_flags & EVAL_EVALUATE);
    typval_T	base = *rettv;
    int		ret;

    rettv->v_type = VAR_UNKNOWN;

    if (**arg == '{')
    {
	// ->{lambda}()
	ret = get_lambda_tv(arg, rettv, FALSE, evalarg);
    }
    else
    {
	// ->(lambda)()
	++*arg;
	ret = eval1(arg, rettv, evalarg);
	*arg = skipwhite_and_linebreak(*arg, evalarg);
	if (**arg != ')')
	{
	    emsg(_(e_missing_closing_paren));
	    return FAIL;
	}
	if (rettv->v_type != VAR_STRING && rettv->v_type != VAR_FUNC
					       && rettv->v_type != VAR_PARTIAL)
	{
	    emsg(_(e_string_or_function_required_for_arrow_parens_expr));
	    return FAIL;
	}
	++*arg;
    }
    if (ret != OK)
	return FAIL;

    if (**arg != '(')
    {
	if (verbose)
	{
	    if (*skipwhite(*arg) == '(')
		emsg(_(e_no_white_space_allowed_before_parenthesis));
	    else
		semsg(_(e_missing_parenthesis_str), "lambda");
	}
	clear_tv(rettv);
	ret = FAIL;
    }
    else
	ret = call_func_rettv(arg, evalarg, rettv, evaluate, NULL, &base);

    // Clear the funcref afterwards, so that deleting it while
    // evaluating the arguments is possible (see test55).
    if (evaluate)
	clear_tv(&base);

    return ret;
}

/*
 * Evaluate "->method()".
 * "*arg" points to "method".
 * Returns FAIL or OK. "*arg" is advanced to after the ')'.
 */
    static int
eval_method(
    char_u	**arg,
    typval_T	*rettv,
    evalarg_T	*evalarg,
    int		verbose)	// give error messages
{
    char_u	*name;
    long	len;
    char_u	*alias;
    char_u	*tofree = NULL;
    typval_T	base = *rettv;
    int		ret = OK;
    int		evaluate = evalarg != NULL
				      && (evalarg->eval_flags & EVAL_EVALUATE);

    rettv->v_type = VAR_UNKNOWN;

    name = *arg;
    len = get_name_len(arg, &alias, evaluate, evaluate);
    if (alias != NULL)
	name = alias;

    if (len <= 0)
    {
	if (verbose)
	    emsg(_(e_missing_name_after_method));
	ret = FAIL;
    }
    else
    {
	char_u *paren;

	// If there is no "(" immediately following, but there is further on,
	// it can be "import.Func()", "dict.Func()", "list[nr]", etc.
	// Does not handle anything where "(" is part of the expression.
	*arg = skipwhite(*arg);

	if (**arg != '(' && alias == NULL
				    && (paren = vim_strchr(*arg, '(')) != NULL)
	{
	    *arg = name;

	    // Truncate the name a the "(".  Avoid trying to get another line
	    // by making "getline" NULL.
	    *paren = NUL;
	    char_u	*(*getline)(int, void *, int, getline_opt_T) = NULL;
	    if (evalarg != NULL)
	    {
		getline = evalarg->eval_getline;
		evalarg->eval_getline = NULL;
	    }

	    char_u *deref = deref_function_name(arg, &tofree, evalarg, verbose);
	    if (deref == NULL)
	    {
		*arg = name + len;
		ret = FAIL;
	    }
	    else
	    {
		name = deref;
		len = (long)STRLEN(name);
	    }

	    *paren = '(';
	    if (getline != NULL)
		evalarg->eval_getline = getline;
	}

	if (ret == OK)
	{
	    *arg = skipwhite(*arg);

	    if (**arg != '(')
	    {
		if (verbose)
		    semsg(_(e_missing_parenthesis_str), name);
		ret = FAIL;
	    }
	    else if (VIM_ISWHITE((*arg)[-1]))
	    {
		if (verbose)
		    emsg(_(e_no_white_space_allowed_before_parenthesis));
		ret = FAIL;
	    }
	    else
		ret = eval_func(arg, evalarg, name, len, rettv,
					  evaluate ? EVAL_EVALUATE : 0, &base);
	}
    }

    // Clear the funcref afterwards, so that deleting it while
    // evaluating the arguments is possible (see test55).
    if (evaluate)
	clear_tv(&base);
    vim_free(tofree);

    return ret;
}

/*
 * Evaluate an "[expr]" or "[expr:expr]" index.  Also "dict.key".
 * "*arg" points to the '[' or '.'.
 * Returns FAIL or OK. "*arg" is advanced to after the ']'.
 */
    static int
eval_index(
    char_u	**arg,
    typval_T	*rettv,
    evalarg_T	*evalarg,
    int		verbose)	// give error messages
{
    int		evaluate = evalarg != NULL
				      && (evalarg->eval_flags & EVAL_EVALUATE);
    int		empty1 = FALSE, empty2 = FALSE;
    typval_T	var1, var2;
    int		range = FALSE;
    char_u	*key = NULL;
    int		keylen = -1;
    int		vim9script = in_vim9script();

    if (check_can_index(rettv, evaluate, verbose) == FAIL)
	return FAIL;

    init_tv(&var1);
    init_tv(&var2);
    if (**arg == '.')
    {
	/*
	 * dict.name
	 */
	key = *arg + 1;
	for (keylen = 0; eval_isdictc(key[keylen]); ++keylen)
	    ;
	if (keylen == 0)
	    return FAIL;
	*arg = key + keylen;
    }
    else
    {
	/*
	 * something[idx]
	 *
	 * Get the (first) variable from inside the [].
	 */
	*arg = skipwhite_and_linebreak(*arg + 1, evalarg);
	if (**arg == ':')
	    empty1 = TRUE;
	else if (eval1(arg, &var1, evalarg) == FAIL)	// recursive!
	    return FAIL;
	else if (vim9script && **arg == ':')
	{
	    semsg(_(e_white_space_required_before_and_after_str_at_str),
								    ":", *arg);
	    clear_tv(&var1);
	    return FAIL;
	}
	else if (evaluate)
	{
	    int error = FALSE;

	    // allow for indexing with float
	    if (vim9script && rettv->v_type == VAR_DICT
						   && var1.v_type == VAR_FLOAT)
	    {
		var1.vval.v_string = typval_tostring(&var1, TRUE);
		var1.v_type = VAR_STRING;
	    }

	    if (vim9script && rettv->v_type == VAR_LIST)
		tv_get_number_chk(&var1, &error);
	    else
		error = tv_get_string_chk(&var1) == NULL;
	    if (error)
	    {
		// not a number or string
		clear_tv(&var1);
		return FAIL;
	    }
	}

	/*
	 * Get the second variable from inside the [:].
	 */
	*arg = skipwhite_and_linebreak(*arg, evalarg);
	if (**arg == ':')
	{
	    range = TRUE;
	    ++*arg;
	    if (vim9script && !IS_WHITE_OR_NUL(**arg) && **arg != ']')
	    {
		semsg(_(e_white_space_required_before_and_after_str_at_str),
								":", *arg - 1);
		if (!empty1)
		    clear_tv(&var1);
		return FAIL;
	    }
	    *arg = skipwhite_and_linebreak(*arg, evalarg);
	    if (**arg == ']')
		empty2 = TRUE;
	    else if (eval1(arg, &var2, evalarg) == FAIL)	// recursive!
	    {
		if (!empty1)
		    clear_tv(&var1);
		return FAIL;
	    }
	    else if (evaluate && tv_get_string_chk(&var2) == NULL)
	    {
		// not a number or string
		if (!empty1)
		    clear_tv(&var1);
		clear_tv(&var2);
		return FAIL;
	    }
	}

	// Check for the ']'.
	*arg = skipwhite_and_linebreak(*arg, evalarg);
	if (**arg != ']')
	{
	    if (verbose)
		emsg(_(e_missing_closing_square_brace));
	    clear_tv(&var1);
	    if (range)
		clear_tv(&var2);
	    return FAIL;
	}
	*arg = *arg + 1;	// skip over the ']'
    }

    if (evaluate)
    {
	int res = eval_index_inner(rettv, range,
		empty1 ? NULL : &var1, empty2 ? NULL : &var2, FALSE,
		key, keylen, verbose);

	if (!empty1)
	    clear_tv(&var1);
	if (range)
	    clear_tv(&var2);
	return res;
    }
    return OK;
}

/*
 * Check if "rettv" can have an [index] or [sli:ce]
 */
    int
check_can_index(typval_T *rettv, int evaluate, int verbose)
{
    switch (rettv->v_type)
    {
	case VAR_FUNC:
	case VAR_PARTIAL:
	    if (verbose)
		emsg(_(e_cannot_index_a_funcref));
	    return FAIL;
	case VAR_FLOAT:
	    if (verbose)
		emsg(_(e_using_float_as_string));
	    return FAIL;
	case VAR_BOOL:
	case VAR_SPECIAL:
	case VAR_JOB:
	case VAR_CHANNEL:
	case VAR_INSTR:
	case VAR_CLASS:
	case VAR_OBJECT:
	    if (verbose)
		emsg(_(e_cannot_index_special_variable));
	    return FAIL;
	case VAR_UNKNOWN:
	case VAR_ANY:
	case VAR_VOID:
	    if (evaluate)
	    {
		emsg(_(e_cannot_index_special_variable));
		return FAIL;
	    }
	    // FALLTHROUGH

	case VAR_STRING:
	case VAR_LIST:
	case VAR_DICT:
	case VAR_BLOB:
	    break;
	case VAR_NUMBER:
	    if (in_vim9script())
		emsg(_(e_cannot_index_number));
	    break;
    }
    return OK;
}

/*
 * slice() function
 */
    void
f_slice(typval_T *argvars, typval_T *rettv)
{
    if (in_vim9script()
	    && ((argvars[0].v_type != VAR_STRING
		    && argvars[0].v_type != VAR_LIST
		    && argvars[0].v_type != VAR_BLOB
		    && check_for_list_arg(argvars, 0) == FAIL)
		|| check_for_number_arg(argvars, 1) == FAIL
		|| check_for_opt_number_arg(argvars, 2) == FAIL))
	return;

    if (check_can_index(argvars, TRUE, FALSE) != OK)
	return;

    copy_tv(argvars, rettv);
    eval_index_inner(rettv, TRUE, argvars + 1,
	    argvars[2].v_type == VAR_UNKNOWN ? NULL : argvars + 2,
	    TRUE, NULL, 0, FALSE);
}

/*
 * Apply index or range to "rettv".
 * "var1" is the first index, NULL for [:expr].
 * "var2" is the second index, NULL for [expr] and [expr: ]
 * "exclusive" is TRUE for slice(): second index is exclusive, use character
 * index for string.
 * Alternatively, "key" is not NULL, then key[keylen] is the dict index.
 */
    int
eval_index_inner(
	typval_T    *rettv,
	int	    is_range,
	typval_T    *var1,
	typval_T    *var2,
	int	    exclusive,
	char_u	    *key,
	int	    keylen,
	int	    verbose)
{
    varnumber_T	    n1, n2 = 0;
    long	    len;

    n1 = 0;
    if (var1 != NULL && rettv->v_type != VAR_DICT)
	n1 = tv_get_number(var1);

    if (is_range)
    {
	if (rettv->v_type == VAR_DICT)
	{
	    if (verbose)
		emsg(_(e_cannot_slice_dictionary));
	    return FAIL;
	}
	if (var2 != NULL)
	    n2 = tv_get_number(var2);
	else
	    n2 = VARNUM_MAX;
    }

    switch (rettv->v_type)
    {
	case VAR_UNKNOWN:
	case VAR_ANY:
	case VAR_VOID:
	case VAR_FUNC:
	case VAR_PARTIAL:
	case VAR_FLOAT:
	case VAR_BOOL:
	case VAR_SPECIAL:
	case VAR_JOB:
	case VAR_CHANNEL:
	case VAR_INSTR:
	case VAR_CLASS:
	case VAR_OBJECT:
	    break; // not evaluating, skipping over subscript

	case VAR_NUMBER:
	case VAR_STRING:
	    {
		char_u	*s = tv_get_string(rettv);

		len = (long)STRLEN(s);
		if (in_vim9script() || exclusive)
		{
		    if (is_range)
			s = string_slice(s, n1, n2, exclusive);
		    else
			s = char_from_string(s, n1);
		}
		else if (is_range)
		{
		    // The resulting variable is a substring.  If the indexes
		    // are out of range the result is empty.
		    if (n1 < 0)
		    {
			n1 = len + n1;
			if (n1 < 0)
			    n1 = 0;
		    }
		    if (n2 < 0)
			n2 = len + n2;
		    else if (n2 >= len)
			n2 = len;
		    if (n1 >= len || n2 < 0 || n1 > n2)
			s = NULL;
		    else
			s = vim_strnsave(s + n1, n2 - n1 + 1);
		}
		else
		{
		    // The resulting variable is a string of a single
		    // character.  If the index is too big or negative the
		    // result is empty.
		    if (n1 >= len || n1 < 0)
			s = NULL;
		    else
			s = vim_strnsave(s + n1, 1);
		}
		clear_tv(rettv);
		rettv->v_type = VAR_STRING;
		rettv->vval.v_string = s;
	    }
	    break;

	case VAR_BLOB:
	    blob_slice_or_index(rettv->vval.v_blob, is_range, n1, n2,
							     exclusive, rettv);
	    break;

	case VAR_LIST:
	    if (var1 == NULL)
		n1 = 0;
	    if (var2 == NULL)
		n2 = VARNUM_MAX;
	    if (list_slice_or_index(rettv->vval.v_list,
			  is_range, n1, n2, exclusive, rettv, verbose) == FAIL)
		return FAIL;
	    break;

	case VAR_DICT:
	    {
		dictitem_T	*item;
		typval_T	tmp;

		if (key == NULL)
		{
		    key = tv_get_string_chk(var1);
		    if (key == NULL)
			return FAIL;
		}

		item = dict_find(rettv->vval.v_dict, key, keylen);

		if (item == NULL)
		{
		    if (verbose)
		    {
			if (keylen > 0)
			    key[keylen] = NUL;
			semsg(_(e_key_not_present_in_dictionary_str), key);
		    }
		    return FAIL;
		}

		copy_tv(&item->di_tv, &tmp);
		clear_tv(rettv);
		*rettv = tmp;
	    }
	    break;
    }
    return OK;
}

/*
 * Return the function name of partial "pt".
 */
    char_u *
partial_name(partial_T *pt)
{
    if (pt != NULL)
    {
	if (pt->pt_name != NULL)
	    return pt->pt_name;
	if (pt->pt_func != NULL)
	    return pt->pt_func->uf_name;
    }
    return (char_u *)"";
}

    static void
partial_free(partial_T *pt)
{
    int i;

    for (i = 0; i < pt->pt_argc; ++i)
	clear_tv(&pt->pt_argv[i]);
    vim_free(pt->pt_argv);
    dict_unref(pt->pt_dict);
    if (pt->pt_name != NULL)
    {
	func_unref(pt->pt_name);
	vim_free(pt->pt_name);
    }
    else
	func_ptr_unref(pt->pt_func);
    object_unref(pt->pt_obj);

    // "out_up" is no longer used, decrement refcount on partial that owns it.
    partial_unref(pt->pt_outer.out_up_partial);

    // Using pt_outer from another partial.
    partial_unref(pt->pt_outer_partial);

    // Decrease the reference count for the context of a closure.  If down
    // to the minimum it may be time to free it.
    if (pt->pt_funcstack != NULL)
    {
	--pt->pt_funcstack->fs_refcount;
	funcstack_check_refcount(pt->pt_funcstack);
    }
    // Similarly for loop variables.
    for (i = 0; i < MAX_LOOP_DEPTH; ++i)
	if (pt->pt_loopvars[i] != NULL)
	{
	    --pt->pt_loopvars[i]->lvs_refcount;
	    loopvars_check_refcount(pt->pt_loopvars[i]);
	}

    vim_free(pt);
}

/*
 * Unreference a closure: decrement the reference count and free it when it
 * becomes zero.
 */
    void
partial_unref(partial_T *pt)
{
    if (pt == NULL)
	return;

    int	done = FALSE;

    if (--pt->pt_refcount <= 0)
	partial_free(pt);

    // If the reference count goes down to one, the funcstack may be the
    // only reference and can be freed if no other partials reference it.
    else if (pt->pt_refcount == 1)
    {
	// careful: if the funcstack is freed it may contain this partial
	// and it gets freed as well
	if (pt->pt_funcstack != NULL)
	    done = funcstack_check_refcount(pt->pt_funcstack);

	if (!done)
	{
	    int	depth;

	    for (depth = 0; depth < MAX_LOOP_DEPTH; ++depth)
		if (pt->pt_loopvars[depth] != NULL
			&& loopvars_check_refcount(pt->pt_loopvars[depth]))
		    break;
	}
    }
}

/*
 * Return the next (unique) copy ID.
 * Used for serializing nested structures.
 */
    int
get_copyID(void)
{
    current_copyID += COPYID_INC;
    return current_copyID;
}

/*
 * Garbage collection for lists and dictionaries.
 *
 * We use reference counts to be able to free most items right away when they
 * are no longer used.  But for composite items it's possible that it becomes
 * unused while the reference count is > 0: When there is a recursive
 * reference.  Example:
 *	:let l = [1, 2, 3]
 *	:let d = {9: l}
 *	:let l[1] = d
 *
 * Since this is quite unusual we handle this with garbage collection: every
 * once in a while find out which lists and dicts are not referenced from any
 * variable.
 *
 * Here is a good reference text about garbage collection (refers to Python
 * but it applies to all reference-counting mechanisms):
 *	http://python.ca/nas/python/gc/
 */

/*
 * Do garbage collection for lists and dicts.
 * When "testing" is TRUE this is called from test_garbagecollect_now().
 * Return TRUE if some memory was freed.
 */
    int
garbage_collect(int testing)
{
    int		copyID;
    int		abort = FALSE;
    buf_T	*buf;
    win_T	*wp;
    int		did_free = FALSE;
    tabpage_T	*tp;

    if (!testing)
    {
	// Only do this once.
	want_garbage_collect = FALSE;
	may_garbage_collect = FALSE;
	garbage_collect_at_exit = FALSE;
    }

    // The execution stack can grow big, limit the size.
    if (exestack.ga_maxlen - exestack.ga_len > 500)
    {
	size_t	new_len;
	char_u	*pp;
	int	n;

	// Keep 150% of the current size, with a minimum of the growth size.
	n = exestack.ga_len / 2;
	if (n < exestack.ga_growsize)
	    n = exestack.ga_growsize;

	// Don't make it bigger though.
	if (exestack.ga_len + n < exestack.ga_maxlen)
	{
	    new_len = (size_t)exestack.ga_itemsize * (exestack.ga_len + n);
	    pp = vim_realloc(exestack.ga_data, new_len);
	    if (pp == NULL)
		return FAIL;
	    exestack.ga_maxlen = exestack.ga_len + n;
	    exestack.ga_data = pp;
	}
    }

    // We advance by two because we add one for items referenced through
    // previous_funccal.
    copyID = get_copyID();

    /*
     * 1. Go through all accessible variables and mark all lists and dicts
     *    with copyID.
     */

    // Don't free variables in the previous_funccal list unless they are only
    // referenced through previous_funccal.  This must be first, because if
    // the item is referenced elsewhere the funccal must not be freed.
    abort = abort || set_ref_in_previous_funccal(copyID);

    // script-local variables
    abort = abort || garbage_collect_scriptvars(copyID);

    // buffer-local variables
    FOR_ALL_BUFFERS(buf)
	abort = abort || set_ref_in_item(&buf->b_bufvar.di_tv, copyID,
								  NULL, NULL);

    // window-local variables
    FOR_ALL_TAB_WINDOWS(tp, wp)
	abort = abort || set_ref_in_item(&wp->w_winvar.di_tv, copyID,
								  NULL, NULL);
    // window-local variables in autocmd windows
    for (int i = 0; i < AUCMD_WIN_COUNT; ++i)
	if (aucmd_win[i].auc_win != NULL)
	    abort = abort || set_ref_in_item(
		    &aucmd_win[i].auc_win->w_winvar.di_tv, copyID, NULL, NULL);
#ifdef FEAT_PROP_POPUP
    FOR_ALL_POPUPWINS(wp)
	abort = abort || set_ref_in_item(&wp->w_winvar.di_tv, copyID,
								  NULL, NULL);
    FOR_ALL_TABPAGES(tp)
	FOR_ALL_POPUPWINS_IN_TAB(tp, wp)
		abort = abort || set_ref_in_item(&wp->w_winvar.di_tv, copyID,
								  NULL, NULL);
#endif

    // tabpage-local variables
    FOR_ALL_TABPAGES(tp)
	abort = abort || set_ref_in_item(&tp->tp_winvar.di_tv, copyID,
								  NULL, NULL);
    // global variables
    abort = abort || garbage_collect_globvars(copyID);

    // function-local variables
    abort = abort || set_ref_in_call_stack(copyID);

    // named functions (matters for closures)
    abort = abort || set_ref_in_functions(copyID);

    // function call arguments, if v:testing is set.
    abort = abort || set_ref_in_func_args(copyID);

    // funcstacks keep variables for closures
    abort = abort || set_ref_in_funcstacks(copyID);

    // loopvars keep variables for loop blocks
    abort = abort || set_ref_in_loopvars(copyID);

    // v: vars
    abort = abort || garbage_collect_vimvars(copyID);

    // callbacks in buffers
    abort = abort || set_ref_in_buffers(copyID);

    // 'completefunc', 'omnifunc' and 'thesaurusfunc' callbacks
    abort = abort || set_ref_in_insexpand_funcs(copyID);

    // 'operatorfunc' callback
    abort = abort || set_ref_in_opfunc(copyID);

    // 'tagfunc' callback
    abort = abort || set_ref_in_tagfunc(copyID);

    // 'imactivatefunc' and 'imstatusfunc' callbacks
    abort = abort || set_ref_in_im_funcs(copyID);

#ifdef FEAT_LUA
    abort = abort || set_ref_in_lua(copyID);
#endif

#ifdef FEAT_PYTHON
    abort = abort || set_ref_in_python(copyID);
#endif

#ifdef FEAT_PYTHON3
    abort = abort || set_ref_in_python3(copyID);
#endif

#ifdef FEAT_JOB_CHANNEL
    abort = abort || set_ref_in_channel(copyID);
    abort = abort || set_ref_in_job(copyID);
#endif
#ifdef FEAT_NETBEANS_INTG
    abort = abort || set_ref_in_nb_channel(copyID);
#endif

#ifdef FEAT_TIMERS
    abort = abort || set_ref_in_timer(copyID);
#endif

#ifdef FEAT_QUICKFIX
    abort = abort || set_ref_in_quickfix(copyID);
#endif

#ifdef FEAT_TERMINAL
    abort = abort || set_ref_in_term(copyID);
#endif

#ifdef FEAT_PROP_POPUP
    abort = abort || set_ref_in_popups(copyID);
#endif

    abort = abort || set_ref_in_classes(copyID);

    if (!abort)
    {
	/*
	 * 2. Free lists and dictionaries that are not referenced.
	 */
	did_free = free_unref_items(copyID);

	/*
	 * 3. Check if any funccal can be freed now.
	 *    This may call us back recursively.
	 */
	free_unref_funccal(copyID, testing);
    }
    else if (p_verbose > 0)
    {
	verb_msg(_("Not enough memory to set references, garbage collection aborted!"));
    }

    return did_free;
}

/*
 * Free lists, dictionaries, channels and jobs that are no longer referenced.
 */
    static int
free_unref_items(int copyID)
{
    int		did_free = FALSE;

    // Let all "free" functions know that we are here.  This means no
    // dictionaries, lists, channels or jobs are to be freed, because we will
    // do that here.
    in_free_unref_items = TRUE;

    /*
     * PASS 1: free the contents of the items.  We don't free the items
     * themselves yet, so that it is possible to decrement refcount counters
     */

    // Go through the list of dicts and free items without this copyID.
    did_free |= dict_free_nonref(copyID);

    // Go through the list of lists and free items without this copyID.
    did_free |= list_free_nonref(copyID);

    // Go through the list of objects and free items without this copyID.
    did_free |= object_free_nonref(copyID);

    // Go through the list of classes and free items without this copyID.
    did_free |= class_free_nonref(copyID);

#ifdef FEAT_JOB_CHANNEL
    // Go through the list of jobs and free items without the copyID. This
    // must happen before doing channels, because jobs refer to channels, but
    // the reference from the channel to the job isn't tracked.
    did_free |= free_unused_jobs_contents(copyID, COPYID_MASK);

    // Go through the list of channels and free items without the copyID.
    did_free |= free_unused_channels_contents(copyID, COPYID_MASK);
#endif

    /*
     * PASS 2: free the items themselves.
     */
    object_free_items(copyID);
    dict_free_items(copyID);
    list_free_items(copyID);

#ifdef FEAT_JOB_CHANNEL
    // Go through the list of jobs and free items without the copyID. This
    // must happen before doing channels, because jobs refer to channels, but
    // the reference from the channel to the job isn't tracked.
    free_unused_jobs(copyID, COPYID_MASK);

    // Go through the list of channels and free items without the copyID.
    free_unused_channels(copyID, COPYID_MASK);
#endif

    in_free_unref_items = FALSE;

    return did_free;
}

/*
 * Mark all lists and dicts referenced through hashtab "ht" with "copyID".
 * "list_stack" is used to add lists to be marked.  Can be NULL.
 *
 * Returns TRUE if setting references failed somehow.
 */
    int
set_ref_in_ht(hashtab_T *ht, int copyID, list_stack_T **list_stack)
{
    int		todo;
    int		abort = FALSE;
    hashitem_T	*hi;
    hashtab_T	*cur_ht;
    ht_stack_T	*ht_stack = NULL;
    ht_stack_T	*tempitem;

    cur_ht = ht;
    for (;;)
    {
	if (!abort)
	{
	    // Mark each item in the hashtab.  If the item contains a hashtab
	    // it is added to ht_stack, if it contains a list it is added to
	    // list_stack.
	    todo = (int)cur_ht->ht_used;
	    FOR_ALL_HASHTAB_ITEMS(cur_ht, hi, todo)
		if (!HASHITEM_EMPTY(hi))
		{
		    --todo;
		    abort = abort || set_ref_in_item(&HI2DI(hi)->di_tv, copyID,
						       &ht_stack, list_stack);
		}
	}

	if (ht_stack == NULL)
	    break;

	// take an item from the stack
	cur_ht = ht_stack->ht;
	tempitem = ht_stack;
	ht_stack = ht_stack->prev;
	free(tempitem);
    }

    return abort;
}

#if defined(FEAT_LUA) || defined(FEAT_PYTHON) || defined(FEAT_PYTHON3) \
							|| defined(PROTO)
/*
 * Mark a dict and its items with "copyID".
 * Returns TRUE if setting references failed somehow.
 */
    int
set_ref_in_dict(dict_T *d, int copyID)
{
    if (d != NULL && d->dv_copyID != copyID)
    {
	d->dv_copyID = copyID;
	return set_ref_in_ht(&d->dv_hashtab, copyID, NULL);
    }
    return FALSE;
}
#endif

/*
 * Mark a list and its items with "copyID".
 * Returns TRUE if setting references failed somehow.
 */
    int
set_ref_in_list(list_T *ll, int copyID)
{
    if (ll != NULL && ll->lv_copyID != copyID)
    {
	ll->lv_copyID = copyID;
	return set_ref_in_list_items(ll, copyID, NULL);
    }
    return FALSE;
}

/*
 * Mark all lists and dicts referenced through list "l" with "copyID".
 * "ht_stack" is used to add hashtabs to be marked.  Can be NULL.
 *
 * Returns TRUE if setting references failed somehow.
 */
    int
set_ref_in_list_items(list_T *l, int copyID, ht_stack_T **ht_stack)
{
    listitem_T	 *li;
    int		 abort = FALSE;
    list_T	 *cur_l;
    list_stack_T *list_stack = NULL;
    list_stack_T *tempitem;

    cur_l = l;
    for (;;)
    {
	if (!abort && cur_l->lv_first != &range_list_item)
	    // Mark each item in the list.  If the item contains a hashtab
	    // it is added to ht_stack, if it contains a list it is added to
	    // list_stack.
	    for (li = cur_l->lv_first; !abort && li != NULL; li = li->li_next)
		abort = abort || set_ref_in_item(&li->li_tv, copyID,
						       ht_stack, &list_stack);
	if (list_stack == NULL)
	    break;

	// take an item from the stack
	cur_l = list_stack->list;
	tempitem = list_stack;
	list_stack = list_stack->prev;
	free(tempitem);
    }

    return abort;
}

/*
 * Mark the partial in callback 'cb' with "copyID".
 */
    int
set_ref_in_callback(callback_T *cb, int copyID)
{
    typval_T tv;

    if (cb->cb_name == NULL || *cb->cb_name == NUL || cb->cb_partial == NULL)
	return FALSE;

    tv.v_type = VAR_PARTIAL;
    tv.vval.v_partial = cb->cb_partial;
    return set_ref_in_item(&tv, copyID, NULL, NULL);
}

/*
 * Mark the dict "dd" with "copyID".
 * Also see set_ref_in_item().
 */
    static int
set_ref_in_item_dict(
    dict_T		*dd,
    int			copyID,
    ht_stack_T		**ht_stack,
    list_stack_T	**list_stack)
{
    if (dd == NULL || dd->dv_copyID == copyID)
	return FALSE;

    // Didn't see this dict yet.
    dd->dv_copyID = copyID;
    if (ht_stack == NULL)
	return set_ref_in_ht(&dd->dv_hashtab, copyID, list_stack);

    ht_stack_T *newitem = ALLOC_ONE(ht_stack_T);
    if (newitem == NULL)
	return TRUE;

    newitem->ht = &dd->dv_hashtab;
    newitem->prev = *ht_stack;
    *ht_stack = newitem;

    return FALSE;
}

/*
 * Mark the list "ll" with "copyID".
 * Also see set_ref_in_item().
 */
    static int
set_ref_in_item_list(
    list_T		*ll,
    int			copyID,
    ht_stack_T		**ht_stack,
    list_stack_T	**list_stack)
{
    if (ll == NULL || ll->lv_copyID == copyID)
	return FALSE;

    // Didn't see this list yet.
    ll->lv_copyID = copyID;
    if (list_stack == NULL)
	return set_ref_in_list_items(ll, copyID, ht_stack);

    list_stack_T *newitem = ALLOC_ONE(list_stack_T);
    if (newitem == NULL)
	return TRUE;

    newitem->list = ll;
    newitem->prev = *list_stack;
    *list_stack = newitem;

    return FALSE;
}

/*
 * Mark the partial "pt" with "copyID".
 * Also see set_ref_in_item().
 */
    static int
set_ref_in_item_partial(
    partial_T		*pt,
    int			copyID,
    ht_stack_T		**ht_stack,
    list_stack_T	**list_stack)
{
    if (pt == NULL || pt->pt_copyID == copyID)
	return FALSE;

    // Didn't see this partial yet.
    pt->pt_copyID = copyID;

    int abort = set_ref_in_func(pt->pt_name, pt->pt_func, copyID);

    if (pt->pt_dict != NULL)
    {
	typval_T dtv;

	dtv.v_type = VAR_DICT;
	dtv.vval.v_dict = pt->pt_dict;
	set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
    }

    if (pt->pt_obj != NULL)
    {
	typval_T objtv;

	objtv.v_type = VAR_OBJECT;
	objtv.vval.v_object = pt->pt_obj;
	set_ref_in_item(&objtv, copyID, ht_stack, list_stack);
    }

    for (int i = 0; i < pt->pt_argc; ++i)
	abort = abort || set_ref_in_item(&pt->pt_argv[i], copyID,
		ht_stack, list_stack);
    // pt_funcstack is handled in set_ref_in_funcstacks()
    // pt_loopvars is handled in set_ref_in_loopvars()

    return abort;
}

#ifdef FEAT_JOB_CHANNEL
/*
 * Mark the job "pt" with "copyID".
 * Also see set_ref_in_item().
 */
    static int
set_ref_in_item_job(
    job_T		*job,
    int			copyID,
    ht_stack_T		**ht_stack,
    list_stack_T	**list_stack)
{
    typval_T    dtv;

    if (job == NULL || job->jv_copyID == copyID)
	return FALSE;

    job->jv_copyID = copyID;
    if (job->jv_channel != NULL)
    {
	dtv.v_type = VAR_CHANNEL;
	dtv.vval.v_channel = job->jv_channel;
	set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
    }
    if (job->jv_exit_cb.cb_partial != NULL)
    {
	dtv.v_type = VAR_PARTIAL;
	dtv.vval.v_partial = job->jv_exit_cb.cb_partial;
	set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
    }

    return FALSE;
}

/*
 * Mark the channel "ch" with "copyID".
 * Also see set_ref_in_item().
 */
    static int
set_ref_in_item_channel(
    channel_T		*ch,
    int			copyID,
    ht_stack_T		**ht_stack,
    list_stack_T	**list_stack)
{
    typval_T    dtv;

    if (ch == NULL || ch->ch_copyID == copyID)
	return FALSE;

    ch->ch_copyID = copyID;
    for (ch_part_T part = PART_SOCK; part < PART_COUNT; ++part)
    {
	for (jsonq_T *jq = ch->ch_part[part].ch_json_head.jq_next;
		jq != NULL; jq = jq->jq_next)
	    set_ref_in_item(jq->jq_value, copyID, ht_stack, list_stack);
	for (cbq_T *cq = ch->ch_part[part].ch_cb_head.cq_next; cq != NULL;
		cq = cq->cq_next)
	    if (cq->cq_callback.cb_partial != NULL)
	    {
		dtv.v_type = VAR_PARTIAL;
		dtv.vval.v_partial = cq->cq_callback.cb_partial;
		set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
	    }
	if (ch->ch_part[part].ch_callback.cb_partial != NULL)
	{
	    dtv.v_type = VAR_PARTIAL;
	    dtv.vval.v_partial = ch->ch_part[part].ch_callback.cb_partial;
	    set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
	}
    }
    if (ch->ch_callback.cb_partial != NULL)
    {
	dtv.v_type = VAR_PARTIAL;
	dtv.vval.v_partial = ch->ch_callback.cb_partial;
	set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
    }
    if (ch->ch_close_cb.cb_partial != NULL)
    {
	dtv.v_type = VAR_PARTIAL;
	dtv.vval.v_partial = ch->ch_close_cb.cb_partial;
	set_ref_in_item(&dtv, copyID, ht_stack, list_stack);
    }

    return FALSE;
}
#endif

/*
 * Mark the class "cl" with "copyID".
 * Also see set_ref_in_item().
 */
    int
set_ref_in_item_class(
    class_T		*cl,
    int			copyID,
    ht_stack_T		**ht_stack,
    list_stack_T	**list_stack)
{
    int abort = FALSE;

    if (cl == NULL || cl->class_copyID == copyID)
	return FALSE;

    cl->class_copyID = copyID;
    if (cl->class_members_tv != NULL)
    {
	// The "class_members_tv" table is allocated only for regular classes
	// and not for interfaces.
	for (int i = 0; !abort && i < cl->class_class_member_count; ++i)
	    abort = abort || set_ref_in_item(
		    &cl->class_members_tv[i],
		    copyID, ht_stack, list_stack);
    }

    for (int i = 0; !abort && i < cl->class_class_function_count; ++i)
	abort = abort || set_ref_in_func(NULL,
		cl->class_class_functions[i], copyID);

    for (int i = 0; !abort && i < cl->class_obj_method_count; ++i)
	abort = abort || set_ref_in_func(NULL,
		cl->class_obj_methods[i], copyID);

    return abort;
}

/*
 * Mark the object "cl" with "copyID".
 * Also see set_ref_in_item().
 */
    static int
set_ref_in_item_object(
    object_T		*obj,
    int			copyID,
    ht_stack_T		**ht_stack,
    list_stack_T	**list_stack)
{
    int abort = FALSE;

    if (obj == NULL || obj->obj_copyID == copyID)
	return FALSE;

    obj->obj_copyID = copyID;

    // The typval_T array is right after the object_T.
    typval_T *mtv = (typval_T *)(obj + 1);
    for (int i = 0; !abort
	    && i < obj->obj_class->class_obj_member_count; ++i)
	abort = abort || set_ref_in_item(mtv + i, copyID,
		ht_stack, list_stack);

    return abort;
}

/*
 * Mark all lists, dicts and other container types referenced through typval
 * "tv" with "copyID".
 * "list_stack" is used to add lists to be marked.  Can be NULL.
 * "ht_stack" is used to add hashtabs to be marked.  Can be NULL.
 *
 * Returns TRUE if setting references failed somehow.
 */
    int
set_ref_in_item(
    typval_T	    *tv,
    int		    copyID,
    ht_stack_T	    **ht_stack,
    list_stack_T    **list_stack)
{
    int		abort = FALSE;

    switch (tv->v_type)
    {
	case VAR_DICT:
	    return set_ref_in_item_dict(tv->vval.v_dict, copyID,
							 ht_stack, list_stack);

	case VAR_LIST:
	    return set_ref_in_item_list(tv->vval.v_list, copyID,
							 ht_stack, list_stack);

	case VAR_FUNC:
	{
	    abort = set_ref_in_func(tv->vval.v_string, NULL, copyID);
	    break;
	}

	case VAR_PARTIAL:
	    return set_ref_in_item_partial(tv->vval.v_partial, copyID,
							ht_stack, list_stack);

	case VAR_JOB:
#ifdef FEAT_JOB_CHANNEL
	    return set_ref_in_item_job(tv->vval.v_job, copyID,
							 ht_stack, list_stack);
#else
	    break;
#endif

	case VAR_CHANNEL:
#ifdef FEAT_JOB_CHANNEL
	    return set_ref_in_item_channel(tv->vval.v_channel, copyID,
							 ht_stack, list_stack);
#else
	    break;
#endif

	case VAR_CLASS:
	    return set_ref_in_item_class(tv->vval.v_class, copyID,
							 ht_stack, list_stack);

	case VAR_OBJECT:
	    return set_ref_in_item_object(tv->vval.v_object, copyID,
							 ht_stack, list_stack);

	case VAR_UNKNOWN:
	case VAR_ANY:
	case VAR_VOID:
	case VAR_BOOL:
	case VAR_SPECIAL:
	case VAR_NUMBER:
	case VAR_FLOAT:
	case VAR_STRING:
	case VAR_BLOB:
	case VAR_INSTR:
	    // Types that do not contain any other item
	    break;
    }

    return abort;
}

/*
 * Return a string with the string representation of a variable.
 * If the memory is allocated "tofree" is set to it, otherwise NULL.
 * "numbuf" is used for a number.
 * When "copyID" is not NULL replace recursive lists and dicts with "...".
 * When both "echo_style" and "composite_val" are FALSE, put quotes around
 * strings as "string()", otherwise does not put quotes around strings, as
 * ":echo" displays values.
 * When "restore_copyID" is FALSE, repeated items in dictionaries and lists
 * are replaced with "...".
 * May return NULL.
 */
    char_u *
echo_string_core(
    typval_T	*tv,
    char_u	**tofree,
    char_u	*numbuf,
    int		copyID,
    int		echo_style,
    int		restore_copyID,
    int		composite_val)
{
    static int	recurse = 0;
    char_u	*r = NULL;

    if (recurse >= DICT_MAXNEST)
    {
	if (!did_echo_string_emsg)
	{
	    // Only give this message once for a recursive call to avoid
	    // flooding the user with errors.  And stop iterating over lists
	    // and dicts.
	    did_echo_string_emsg = TRUE;
	    emsg(_(e_variable_nested_too_deep_for_displaying));
	}
	*tofree = NULL;
	return (char_u *)"{E724}";
    }
    ++recurse;

    switch (tv->v_type)
    {
	case VAR_STRING:
	    if (echo_style && !composite_val)
	    {
		*tofree = NULL;
		r = tv->vval.v_string;
		if (r == NULL)
		    r = (char_u *)"";
	    }
	    else
	    {
		*tofree = string_quote(tv->vval.v_string, FALSE);
		r = *tofree;
	    }
	    break;

	case VAR_FUNC:
	    {
		char_u buf[MAX_FUNC_NAME_LEN];

		if (echo_style)
		{
		    r = tv->vval.v_string == NULL ? (char_u *)"function()"
				  : make_ufunc_name_readable(tv->vval.v_string,
						       buf, MAX_FUNC_NAME_LEN);
		    if (r == buf)
		    {
			r = vim_strsave(buf);
			*tofree = r;
		    }
		    else
			*tofree = NULL;
		}
		else
		{
		    *tofree = string_quote(tv->vval.v_string == NULL ? NULL
			    : make_ufunc_name_readable(
				tv->vval.v_string, buf, MAX_FUNC_NAME_LEN),
									 TRUE);
		    r = *tofree;
		}
	    }
	    break;

	case VAR_PARTIAL:
	    {
		partial_T   *pt = tv->vval.v_partial;
		char_u	    *fname = string_quote(pt == NULL ? NULL
						    : partial_name(pt), FALSE);
		garray_T    ga;
		int	    i;
		char_u	    *tf;

		ga_init2(&ga, 1, 100);
		ga_concat(&ga, (char_u *)"function(");
		if (fname != NULL)
		{
		    // When using uf_name prepend "g:" for a global function.
		    if (pt != NULL && pt->pt_name == NULL && fname[0] == '\''
						      && vim_isupper(fname[1]))
		    {
			ga_concat(&ga, (char_u *)"'g:");
			ga_concat(&ga, fname + 1);
		    }
		    else
			ga_concat(&ga, fname);
		    vim_free(fname);
		}
		if (pt != NULL && pt->pt_argc > 0)
		{
		    ga_concat(&ga, (char_u *)", [");
		    for (i = 0; i < pt->pt_argc; ++i)
		    {
			if (i > 0)
			    ga_concat(&ga, (char_u *)", ");
			ga_concat(&ga,
			     tv2string(&pt->pt_argv[i], &tf, numbuf, copyID));
			vim_free(tf);
		    }
		    ga_concat(&ga, (char_u *)"]");
		}
		if (pt != NULL && pt->pt_dict != NULL)
		{
		    typval_T dtv;

		    ga_concat(&ga, (char_u *)", ");
		    dtv.v_type = VAR_DICT;
		    dtv.vval.v_dict = pt->pt_dict;
		    ga_concat(&ga, tv2string(&dtv, &tf, numbuf, copyID));
		    vim_free(tf);
		}
		// terminate with ')' and a NUL
		ga_concat_len(&ga, (char_u *)")", 2);

		*tofree = ga.ga_data;
		r = *tofree;
		break;
	    }

	case VAR_BLOB:
	    r = blob2string(tv->vval.v_blob, tofree, numbuf);
	    break;

	case VAR_LIST:
	    if (tv->vval.v_list == NULL)
	    {
		// NULL list is equivalent to empty list.
		*tofree = NULL;
		r = (char_u *)"[]";
	    }
	    else if (copyID != 0 && tv->vval.v_list->lv_copyID == copyID
		    && tv->vval.v_list->lv_len > 0)
	    {
		*tofree = NULL;
		r = (char_u *)"[...]";
	    }
	    else
	    {
		int old_copyID = tv->vval.v_list->lv_copyID;

		tv->vval.v_list->lv_copyID = copyID;
		*tofree = list2string(tv, copyID, restore_copyID);
		if (restore_copyID)
		    tv->vval.v_list->lv_copyID = old_copyID;
		r = *tofree;
	    }
	    break;

	case VAR_DICT:
	    if (tv->vval.v_dict == NULL)
	    {
		// NULL dict is equivalent to empty dict.
		*tofree = NULL;
		r = (char_u *)"{}";
	    }
	    else if (copyID != 0 && tv->vval.v_dict->dv_copyID == copyID
		    && tv->vval.v_dict->dv_hashtab.ht_used != 0)
	    {
		*tofree = NULL;
		r = (char_u *)"{...}";
	    }
	    else
	    {
		int old_copyID = tv->vval.v_dict->dv_copyID;

		tv->vval.v_dict->dv_copyID = copyID;
		*tofree = dict2string(tv, copyID, restore_copyID);
		if (restore_copyID)
		    tv->vval.v_dict->dv_copyID = old_copyID;
		r = *tofree;
	    }
	    break;

	case VAR_NUMBER:
	case VAR_UNKNOWN:
	case VAR_ANY:
	case VAR_VOID:
	    *tofree = NULL;
	    r = tv_get_string_buf(tv, numbuf);
	    break;

	case VAR_JOB:
	case VAR_CHANNEL:
#ifdef FEAT_JOB_CHANNEL
	    *tofree = NULL;
	    r = tv->v_type == VAR_JOB ? job_to_string_buf(tv, numbuf)
					   : channel_to_string_buf(tv, numbuf);
	    if (composite_val)
	    {
		*tofree = string_quote(r, FALSE);
		r = *tofree;
	    }
#endif
	    break;

	case VAR_INSTR:
	    *tofree = NULL;
	    r = (char_u *)"instructions";
	    break;

	case VAR_CLASS:
	    {
		class_T *cl = tv->vval.v_class;
		size_t len = 6 + (cl == NULL ? 9 : STRLEN(cl->class_name)) + 1;
		r = *tofree = alloc(len);
		vim_snprintf((char *)r, len, "class %s",
			    cl == NULL ? "[unknown]" : (char *)cl->class_name);
	    }
	    break;

	case VAR_OBJECT:
	    {
		garray_T ga;
		ga_init2(&ga, 1, 50);
		ga_concat(&ga, (char_u *)"object of ");
		object_T *obj = tv->vval.v_object;
		class_T *cl = obj == NULL ? NULL : obj->obj_class;
		ga_concat(&ga, cl == NULL ? (char_u *)"[unknown]"
							     : cl->class_name);
		if (cl != NULL)
		{
		    ga_concat(&ga, (char_u *)" {");
		    for (int i = 0; i < cl->class_obj_member_count; ++i)
		    {
			if (i > 0)
			    ga_concat(&ga, (char_u *)", ");
			ocmember_T *m = &cl->class_obj_members[i];
			ga_concat(&ga, m->ocm_name);
			ga_concat(&ga, (char_u *)": ");
			char_u *tf = NULL;
			ga_concat(&ga, echo_string_core(
					       (typval_T *)(obj + 1) + i,
					       &tf, numbuf, copyID, echo_style,
					       restore_copyID, composite_val));
			vim_free(tf);
		    }
		    ga_concat(&ga, (char_u *)"}");
		}

		*tofree = r = ga.ga_data;
	    }
	    break;

	case VAR_FLOAT:
	    *tofree = NULL;
	    vim_snprintf((char *)numbuf, NUMBUFLEN, "%g", tv->vval.v_float);
	    r = numbuf;
	    break;

	case VAR_BOOL:
	case VAR_SPECIAL:
	    *tofree = NULL;
	    r = (char_u *)get_var_special_name(tv->vval.v_number);
	    break;
    }

    if (--recurse == 0)
	did_echo_string_emsg = FALSE;
    return r;
}

/*
 * Return a string with the string representation of a variable.
 * If the memory is allocated "tofree" is set to it, otherwise NULL.
 * "numbuf" is used for a number.
 * Does not put quotes around strings, as ":echo" displays values.
 * When "copyID" is not NULL replace recursive lists and dicts with "...".
 * May return NULL.
 */
    char_u *
echo_string(
    typval_T	*tv,
    char_u	**tofree,
    char_u	*numbuf,
    int		copyID)
{
    return echo_string_core(tv, tofree, numbuf, copyID, TRUE, FALSE, FALSE);
}

/*
 * Convert the specified byte index of line 'lnum' in buffer 'buf' to a
 * character index.  Works only for loaded buffers. Returns -1 on failure.
 * The index of the first byte and the first character is zero.
 */
    int
buf_byteidx_to_charidx(buf_T *buf, int lnum, int byteidx)
{
    char_u	*str;
    char_u	*t;
    int		count;

    if (buf == NULL || buf->b_ml.ml_mfp == NULL)
	return -1;

    if (lnum > buf->b_ml.ml_line_count)
	lnum = buf->b_ml.ml_line_count;

    str = ml_get_buf(buf, lnum, FALSE);
    if (str == NULL)
	return -1;

    if (*str == NUL)
	return 0;

    // count the number of characters
    t = str;
    for (count = 0; *t != NUL && t <= str + byteidx; count++)
	t += mb_ptr2len(t);

    // In insert mode, when the cursor is at the end of a non-empty line,
    // byteidx points to the NUL character immediately past the end of the
    // string. In this case, add one to the character count.
    if (*t == NUL && byteidx != 0 && t == str + byteidx)
	count++;

    return count - 1;
}

/*
 * Convert the specified character index of line 'lnum' in buffer 'buf' to a
 * byte index.  Works only for loaded buffers. Returns -1 on failure.
 * The index of the first byte and the first character is zero.
 */
    int
buf_charidx_to_byteidx(buf_T *buf, int lnum, int charidx)
{
    char_u	*str;
    char_u	*t;

    if (buf == NULL || buf->b_ml.ml_mfp == NULL)
	return -1;

    if (lnum > buf->b_ml.ml_line_count)
	lnum = buf->b_ml.ml_line_count;

    str = ml_get_buf(buf, lnum, FALSE);
    if (str == NULL)
	return -1;

    // Convert the character offset to a byte offset
    t = str;
    while (*t != NUL && --charidx > 0)
	t += mb_ptr2len(t);

    return t - str;
}

/*
 * Translate a String variable into a position.
 * Returns NULL when there is an error.
 */
    pos_T *
var2fpos(
    typval_T	*varp,
    int		dollar_lnum,	// TRUE when $ is last line
    int		*fnum,		// set to fnum for '0, 'A, etc.
    int		charcol)	// return character column
{
    char_u		*name;
    static pos_T	pos;
    pos_T		*pp;

    // Argument can be [lnum, col, coladd].
    if (varp->v_type == VAR_LIST)
    {
	list_T		*l;
	int		len;
	int		error = FALSE;
	listitem_T	*li;

	l = varp->vval.v_list;
	if (l == NULL)
	    return NULL;

	// Get the line number
	pos.lnum = list_find_nr(l, 0L, &error);
	if (error || pos.lnum <= 0 || pos.lnum > curbuf->b_ml.ml_line_count)
	    return NULL;	// invalid line number
	if (charcol)
	    len = (long)mb_charlen(ml_get(pos.lnum));
	else
	    len = (long)STRLEN(ml_get(pos.lnum));

	// Get the column number
	// We accept "$" for the column number: last column.
	li = list_find(l, 1L);
	if (li != NULL && li->li_tv.v_type == VAR_STRING
		&& li->li_tv.vval.v_string != NULL
		&& STRCMP(li->li_tv.vval.v_string, "$") == 0)
	{
	    pos.col = len + 1;
	}
	else
	{
	    pos.col = list_find_nr(l, 1L, &error);
	    if (error)
		return NULL;
	}

	// Accept a position up to the NUL after the line.
	if (pos.col == 0 || (int)pos.col > len + 1)
	    return NULL;	// invalid column number
	--pos.col;

	// Get the virtual offset.  Defaults to zero.
	pos.coladd = list_find_nr(l, 2L, &error);
	if (error)
	    pos.coladd = 0;

	return &pos;
    }

    if (in_vim9script() && check_for_string_arg(varp, 0) == FAIL)
	return NULL;

    name = tv_get_string_chk(varp);
    if (name == NULL)
	return NULL;

    pos.lnum = 0;
    if (name[0] == '.' && (!in_vim9script() || name[1] == NUL))
    {
	// cursor
	pos = curwin->w_cursor;
    }
    else if (name[0] == 'v' && name[1] == NUL)
    {
	// Visual start
	if (VIsual_active)
	    pos = VIsual;
	else
	    pos = curwin->w_cursor;
    }
    else if (name[0] == '\'' && (!in_vim9script()
					|| (name[1] != NUL && name[2] == NUL)))
    {
	// mark
	pp = getmark_buf_fnum(curbuf, name[1], FALSE, fnum);
	if (pp == NULL || pp == (pos_T *)-1 || pp->lnum <= 0)
	    return NULL;
	pos = *pp;
    }
    if (pos.lnum != 0)
    {
	if (charcol)
	    pos.col = buf_byteidx_to_charidx(curbuf, pos.lnum, pos.col);
	return &pos;
    }

    pos.coladd = 0;

    if (name[0] == 'w' && dollar_lnum)
    {
	// the "w_valid" flags are not reset when moving the cursor, but they
	// do matter for update_topline() and validate_botline().
	check_cursor_moved(curwin);

	pos.col = 0;
	if (name[1] == '0')		// "w0": first visible line
	{
	    update_topline();
	    // In silent Ex mode topline is zero, but that's not a valid line
	    // number; use one instead.
	    pos.lnum = curwin->w_topline > 0 ? curwin->w_topline : 1;
	    return &pos;
	}
	else if (name[1] == '$')	// "w$": last visible line
	{
	    validate_botline();
	    // In silent Ex mode botline is zero, return zero then.
	    pos.lnum = curwin->w_botline > 0 ? curwin->w_botline - 1 : 0;
	    return &pos;
	}
    }
    else if (name[0] == '$')		// last column or line
    {
	if (dollar_lnum)
	{
	    pos.lnum = curbuf->b_ml.ml_line_count;
	    pos.col = 0;
	}
	else
	{
	    pos.lnum = curwin->w_cursor.lnum;
	    if (charcol)
		pos.col = (colnr_T)mb_charlen(ml_get_curline());
	    else
		pos.col = (colnr_T)STRLEN(ml_get_curline());
	}
	return &pos;
    }
    if (in_vim9script())
	semsg(_(e_invalid_value_for_line_number_str), name);
    return NULL;
}

/*
 * Convert list in "arg" into position "posp" and optional file number "fnump".
 * When "fnump" is NULL there is no file number, only 3 items: [lnum, col, off]
 * Note that the column is passed on as-is, the caller may want to decrement
 * it to use 1 for the first column.
 * If "charcol" is TRUE use the column as the character index instead of the
 * byte index.
 * Return FAIL when conversion is not possible, doesn't check the position for
 * validity.
 */
    int
list2fpos(
    typval_T	*arg,
    pos_T	*posp,
    int		*fnump,
    colnr_T	*curswantp,
    int		charcol)
{
    list_T	*l = arg->vval.v_list;
    long	i = 0;
    long	n;

    // List must be: [fnum, lnum, col, coladd, curswant], where "fnum" is only
    // there when "fnump" isn't NULL; "coladd" and "curswant" are optional.
    if (arg->v_type != VAR_LIST
	    || l == NULL
	    || l->lv_len < (fnump == NULL ? 2 : 3)
	    || l->lv_len > (fnump == NULL ? 4 : 5))
	return FAIL;

    if (fnump != NULL)
    {
	n = list_find_nr(l, i++, NULL);	// fnum
	if (n < 0)
	    return FAIL;
	if (n == 0)
	    n = curbuf->b_fnum;		// current buffer
	*fnump = n;
    }

    n = list_find_nr(l, i++, NULL);	// lnum
    if (n < 0)
	return FAIL;
    posp->lnum = n;

    n = list_find_nr(l, i++, NULL);	// col
    if (n < 0)
	return FAIL;
    // If character position is specified, then convert to byte position
    // If the line number is zero use the cursor line.
    if (charcol)
    {
	buf_T	*buf;

	// Get the text for the specified line in a loaded buffer
	buf = buflist_findnr(fnump == NULL ? curbuf->b_fnum : *fnump);
	if (buf == NULL || buf->b_ml.ml_mfp == NULL)
	    return FAIL;

	n = buf_charidx_to_byteidx(buf,
		  posp->lnum == 0 ? curwin->w_cursor.lnum : posp->lnum, n) + 1;
    }
    posp->col = n;

    n = list_find_nr(l, i, NULL);	// off
    if (n < 0)
	posp->coladd = 0;
    else
	posp->coladd = n;

    if (curswantp != NULL)
	*curswantp = list_find_nr(l, i + 1, NULL);  // curswant

    return OK;
}

/*
 * Get the length of an environment variable name.
 * Advance "arg" to the first character after the name.
 * Return 0 for error.
 */
    int
get_env_len(char_u **arg)
{
    char_u	*p;
    int		len;

    for (p = *arg; vim_isIDc(*p); ++p)
	;
    if (p == *arg)	    // no name found
	return 0;

    len = (int)(p - *arg);
    *arg = p;
    return len;
}

/*
 * Get the length of the name of a function or internal variable.
 * "arg" is advanced to after the name.
 * Return 0 if something is wrong.
 */
    int
get_id_len(char_u **arg)
{
    char_u	*p;
    int		len;

    // Find the end of the name.
    for (p = *arg; eval_isnamec(*p); ++p)
    {
	if (*p == ':')
	{
	    // "s:" is start of "s:var", but "n:" is not and can be used in
	    // slice "[n:]".  Also "xx:" is not a namespace.
	    len = (int)(p - *arg);
	    if ((len == 1 && vim_strchr(NAMESPACE_CHAR, **arg) == NULL)
		    || len > 1)
		break;
	}
    }
    if (p == *arg)	    // no name found
	return 0;

    len = (int)(p - *arg);
    *arg = p;

    return len;
}

/*
 * Get the length of the name of a variable or function.
 * Only the name is recognized, does not handle ".key" or "[idx]".
 * "arg" is advanced to the first non-white character after the name.
 * Return -1 if curly braces expansion failed.
 * Return 0 if something else is wrong.
 * If the name contains 'magic' {}'s, expand them and return the
 * expanded name in an allocated string via 'alias' - caller must free.
 */
    int
get_name_len(
    char_u	**arg,
    char_u	**alias,
    int		evaluate,
    int		verbose)
{
    int		len;
    char_u	*p;
    char_u	*expr_start;
    char_u	*expr_end;

    *alias = NULL;  // default to no alias

    if ((*arg)[0] == K_SPECIAL && (*arg)[1] == KS_EXTRA
						  && (*arg)[2] == (int)KE_SNR)
    {
	// hard coded <SNR>, already translated
	*arg += 3;
	return get_id_len(arg) + 3;
    }
    len = eval_fname_script(*arg);
    if (len > 0)
    {
	// literal "<SID>", "s:" or "<SNR>"
	*arg += len;
    }

    /*
     * Find the end of the name; check for {} construction.
     */
    p = find_name_end(*arg, &expr_start, &expr_end,
					       len > 0 ? 0 : FNE_CHECK_START);
    if (expr_start != NULL)
    {
	char_u	*temp_string;

	if (!evaluate)
	{
	    len += (int)(p - *arg);
	    *arg = skipwhite(p);
	    return len;
	}

	/*
	 * Include any <SID> etc in the expanded string:
	 * Thus the -len here.
	 */
	temp_string = make_expanded_name(*arg - len, expr_start, expr_end, p);
	if (temp_string == NULL)
	    return -1;
	*alias = temp_string;
	*arg = skipwhite(p);
	return (int)STRLEN(temp_string);
    }

    len += get_id_len(arg);
    // Only give an error when there is something, otherwise it will be
    // reported at a higher level.
    if (len == 0 && verbose && **arg != NUL)
	semsg(_(e_invalid_expression_str), *arg);

    return len;
}

/*
 * Find the end of a variable or function name, taking care of magic braces.
 * If "expr_start" is not NULL then "expr_start" and "expr_end" are set to the
 * start and end of the first magic braces item.
 * "flags" can have FNE_INCL_BR and FNE_CHECK_START.
 * Return a pointer to just after the name.  Equal to "arg" if there is no
 * valid name.
 */
    char_u *
find_name_end(
    char_u	*arg,
    char_u	**expr_start,
    char_u	**expr_end,
    int		flags)
{
    int		mb_nest = 0;
    int		br_nest = 0;
    char_u	*p;
    int		len;
    int		allow_curly = (flags & FNE_ALLOW_CURLY) || !in_vim9script();

    if (expr_start != NULL)
    {
	*expr_start = NULL;
	*expr_end = NULL;
    }

    // Quick check for valid starting character.
    if ((flags & FNE_CHECK_START) && !eval_isnamec1(*arg)
					      && (*arg != '{' || !allow_curly))
	return arg;

    for (p = arg; *p != NUL
		    && (eval_isnamec(*p)
			|| (*p == '{' && allow_curly)
			|| ((flags & FNE_INCL_BR) && (*p == '['
					 || (*p == '.' && eval_isdictc(p[1]))))
			|| mb_nest != 0
			|| br_nest != 0); MB_PTR_ADV(p))
    {
	if (*p == '\'')
	{
	    // skip over 'string' to avoid counting [ and ] inside it.
	    for (p = p + 1; *p != NUL && *p != '\''; MB_PTR_ADV(p))
		;
	    if (*p == NUL)
		break;
	}
	else if (*p == '"')
	{
	    // skip over "str\"ing" to avoid counting [ and ] inside it.
	    for (p = p + 1; *p != NUL && *p != '"'; MB_PTR_ADV(p))
		if (*p == '\\' && p[1] != NUL)
		    ++p;
	    if (*p == NUL)
		break;
	}
	else if (br_nest == 0 && mb_nest == 0 && *p == ':')
	{
	    // "s:" is start of "s:var", but "n:" is not and can be used in
	    // slice "[n:]".  Also "xx:" is not a namespace. But {ns}: is.
	    len = (int)(p - arg);
	    if ((len == 1 && vim_strchr(NAMESPACE_CHAR, *arg) == NULL)
		    || (len > 1 && p[-1] != '}'))
		break;
	}

	if (mb_nest == 0)
	{
	    if (*p == '[')
		++br_nest;
	    else if (*p == ']')
		--br_nest;
	}

	if (br_nest == 0 && allow_curly)
	{
	    if (*p == '{')
	    {
		mb_nest++;
		if (expr_start != NULL && *expr_start == NULL)
		    *expr_start = p;
	    }
	    else if (*p == '}')
	    {
		mb_nest--;
		if (expr_start != NULL && mb_nest == 0 && *expr_end == NULL)
		    *expr_end = p;
	    }
	}
    }

    return p;
}

/*
 * Expands out the 'magic' {}'s in a variable/function name.
 * Note that this can call itself recursively, to deal with
 * constructs like foo{bar}{baz}{bam}
 * The four pointer arguments point to "foo{expre}ss{ion}bar"
 *			"in_start"      ^
 *			"expr_start"	   ^
 *			"expr_end"		 ^
 *			"in_end"			    ^
 *
 * Returns a new allocated string, which the caller must free.
 * Returns NULL for failure.
 */
    static char_u *
make_expanded_name(
    char_u	*in_start,
    char_u	*expr_start,
    char_u	*expr_end,
    char_u	*in_end)
{
    char_u	c1;
    char_u	*retval = NULL;
    char_u	*temp_result;

    if (expr_end == NULL || in_end == NULL)
	return NULL;
    *expr_start	= NUL;
    *expr_end = NUL;
    c1 = *in_end;
    *in_end = NUL;

    temp_result = eval_to_string(expr_start + 1, FALSE, FALSE);
    if (temp_result != NULL)
    {
	retval = alloc(STRLEN(temp_result) + (expr_start - in_start)
						   + (in_end - expr_end) + 1);
	if (retval != NULL)
	{
	    STRCPY(retval, in_start);
	    STRCAT(retval, temp_result);
	    STRCAT(retval, expr_end + 1);
	}
    }
    vim_free(temp_result);

    *in_end = c1;		// put char back for error messages
    *expr_start = '{';
    *expr_end = '}';

    if (retval != NULL)
    {
	temp_result = find_name_end(retval, &expr_start, &expr_end, 0);
	if (expr_start != NULL)
	{
	    // Further expansion!
	    temp_result = make_expanded_name(retval, expr_start,
						       expr_end, temp_result);
	    vim_free(retval);
	    retval = temp_result;
	}
    }

    return retval;
}

/*
 * Return TRUE if character "c" can be used in a variable or function name.
 * Does not include '{' or '}' for magic braces.
 */
    int
eval_isnamec(int c)
{
    return ASCII_ISALNUM(c) || c == '_' || c == ':' || c == AUTOLOAD_CHAR;
}

/*
 * Return TRUE if character "c" can be used as the first character in a
 * variable or function name (excluding '{' and '}').
 */
    int
eval_isnamec1(int c)
{
    return ASCII_ISALPHA(c) || c == '_';
}

/*
 * Return TRUE if character "c" can be used as the first character of a
 * dictionary key.
 */
    int
eval_isdictc(int c)
{
    return ASCII_ISALNUM(c) || c == '_';
}

/*
 * Handle:
 * - expr[expr], expr[expr:expr] subscript
 * - ".name" lookup
 * - function call with Funcref variable: func(expr)
 * - method call: var->method()
 *
 * Can all be combined in any order: dict.func(expr)[idx]['func'](expr)->len()
 * "name_start" points to a variable before the subscript or is NULL.
 */
    int
handle_subscript(
    char_u	**arg,
    char_u	*name_start,
    typval_T	*rettv,
    evalarg_T	*evalarg,
    int		verbose)	// give error messages
{
    int		evaluate = evalarg != NULL
				      && (evalarg->eval_flags & EVAL_EVALUATE);
    int		ret = OK;
    dict_T	*selfdict = NULL;
    int		check_white = TRUE;
    int		getnext;
    char_u	*p;

    while (ret == OK)
    {
	// When at the end of the line and ".name" or "->{" or "->X" follows in
	// the next line then consume the line break.
	p = eval_next_non_blank(*arg, evalarg, &getnext);
	if (getnext
	    && ((*p == '.'
		    && ((rettv->v_type == VAR_DICT && eval_isdictc(p[1]))
			|| rettv->v_type == VAR_CLASS
			|| rettv->v_type == VAR_OBJECT))
		|| (p[0] == '-' && p[1] == '>' && (p[2] == '{'
			|| ASCII_ISALPHA(in_vim9script() ? *skipwhite(p + 2)
								    : p[2])))))
	{
	    *arg = eval_next_line(*arg, evalarg);
	    p = *arg;
	    check_white = FALSE;
	}

	if (rettv->v_type == VAR_ANY)
	{
	    char_u	*exp_name;
	    int		cc;
	    int		idx;
	    ufunc_T	*ufunc;
	    type_T	*type;

	    // Found script from "import {name} as name", script item name must
	    // follow.  "rettv->vval.v_number" has the script ID.
	    if (**arg != '.')
	    {
		if (verbose)
		    semsg(_(e_expected_dot_after_name_str),
					name_start != NULL ? name_start: *arg);
		ret = FAIL;
		break;
	    }
	    ++*arg;
	    if (IS_WHITE_OR_NUL(**arg))
	    {
		if (verbose)
		    emsg(_(e_no_white_space_allowed_after_dot));
		ret = FAIL;
		break;
	    }

	    // isolate the name
	    exp_name = *arg;
	    while (eval_isnamec(**arg))
		++*arg;
	    cc = **arg;
	    **arg = NUL;

	    idx = find_exported(rettv->vval.v_number, exp_name, &ufunc, &type,
		       evalarg == NULL ? NULL : evalarg->eval_cctx,
		       evalarg == NULL ? NULL : evalarg->eval_cstack, verbose);
	    **arg = cc;

	    if (idx < 0 && ufunc == NULL)
	    {
		ret = FAIL;
		break;
	    }
	    if (idx >= 0)
	    {
		scriptitem_T    *si = SCRIPT_ITEM(rettv->vval.v_number);
		svar_T		*sv = ((svar_T *)si->sn_var_vals.ga_data) + idx;

		copy_tv(sv->sv_tv, rettv);
	    }
	    else
	    {
		rettv->v_type = VAR_FUNC;
		rettv->vval.v_string = vim_strsave(ufunc->uf_name);
	    }
	    continue;
	}

	if ((**arg == '(' && (!evaluate || rettv->v_type == VAR_FUNC
			    || rettv->v_type == VAR_PARTIAL))
		    && (!check_white || !VIM_ISWHITE(*(*arg - 1))))
	{
	    ret = call_func_rettv(arg, evalarg, rettv, evaluate,
							       selfdict, NULL);

	    // Stop the expression evaluation when immediately aborting on
	    // error, or when an interrupt occurred or an exception was thrown
	    // but not caught.
	    if (aborting())
	    {
		if (ret == OK)
		    clear_tv(rettv);
		ret = FAIL;
	    }
	    dict_unref(selfdict);
	    selfdict = NULL;
	}
	else if (p[0] == '-' && p[1] == '>')
	{
	    if (in_vim9script())
		*arg = skipwhite(p + 2);
	    else
		*arg = p + 2;
	    if (VIM_ISWHITE(**arg))
	    {
		emsg(_(e_no_white_space_allowed_before_parenthesis));
		ret = FAIL;
	    }
	    else if ((**arg == '{' && !in_vim9script()) || **arg == '(')
		// expr->{lambda}() or expr->(lambda)()
		ret = eval_lambda(arg, rettv, evalarg, verbose);
	    else
		// expr->name()
		ret = eval_method(arg, rettv, evalarg, verbose);
	}
	// "." is ".name" lookup when we found a dict or when evaluating and
	// scriptversion is at least 2, where string concatenation is "..".
	else if (**arg == '['
		|| (**arg == '.' && (rettv->v_type == VAR_DICT
			|| (!evaluate
			    && (*arg)[1] != '.'
			    && !in_old_script(2)))))
	{
	    dict_unref(selfdict);
	    if (rettv->v_type == VAR_DICT)
	    {
		selfdict = rettv->vval.v_dict;
		if (selfdict != NULL)
		    ++selfdict->dv_refcount;
	    }
	    else
		selfdict = NULL;
	    if (eval_index(arg, rettv, evalarg, verbose) == FAIL)
	    {
		clear_tv(rettv);
		ret = FAIL;
	    }
	}
	else if (**arg == '.' && (rettv->v_type == VAR_CLASS
					       || rettv->v_type == VAR_OBJECT))
	{
	    // class member: SomeClass.varname
	    // class method: SomeClass.SomeMethod()
	    // class constructor: SomeClass.new()
	    // object member: someObject.varname
	    // object method: someObject.SomeMethod()
	    if (class_object_index(arg, rettv, evalarg, verbose) == FAIL)
	    {
		clear_tv(rettv);
		ret = FAIL;
	    }
	}
	else
	    break;
    }

    // Turn "dict.Func" into a partial for "Func" bound to "dict".
    // Don't do this when "Func" is already a partial that was bound
    // explicitly (pt_auto is FALSE).
    if (selfdict != NULL
	    && (rettv->v_type == VAR_FUNC
		|| (rettv->v_type == VAR_PARTIAL
		    && (rettv->vval.v_partial->pt_auto
			|| rettv->vval.v_partial->pt_dict == NULL))))
	selfdict = make_partial(selfdict, rettv);

    dict_unref(selfdict);
    return ret;
}

/*
 * Make a copy of an item.
 * Lists and Dictionaries are also copied.  A deep copy if "deep" is set.
 * "top" is TRUE for the toplevel of copy().
 * For deepcopy() "copyID" is zero for a full copy or the ID for when a
 * reference to an already copied list/dict can be used.
 * Returns FAIL or OK.
 */
    int
item_copy(
    typval_T	*from,
    typval_T	*to,
    int		deep,
    int		top,
    int		copyID)
{
    static int	recurse = 0;
    int		ret = OK;

    if (recurse >= DICT_MAXNEST)
    {
	emsg(_(e_variable_nested_too_deep_for_making_copy));
	return FAIL;
    }
    ++recurse;

    switch (from->v_type)
    {
	case VAR_NUMBER:
	case VAR_FLOAT:
	case VAR_STRING:
	case VAR_FUNC:
	case VAR_PARTIAL:
	case VAR_BOOL:
	case VAR_SPECIAL:
	case VAR_JOB:
	case VAR_CHANNEL:
	case VAR_INSTR:
	case VAR_CLASS:
	case VAR_OBJECT:
	    copy_tv(from, to);
	    break;
	case VAR_LIST:
	    to->v_type = VAR_LIST;
	    to->v_lock = 0;
	    if (from->vval.v_list == NULL)
		to->vval.v_list = NULL;
	    else if (copyID != 0 && from->vval.v_list->lv_copyID == copyID)
	    {
		// use the copy made earlier
		to->vval.v_list = from->vval.v_list->lv_copylist;
		++to->vval.v_list->lv_refcount;
	    }
	    else
		to->vval.v_list = list_copy(from->vval.v_list,
							    deep, top, copyID);
	    if (to->vval.v_list == NULL)
		ret = FAIL;
	    break;
	case VAR_BLOB:
	    ret = blob_copy(from->vval.v_blob, to);
	    break;
	case VAR_DICT:
	    to->v_type = VAR_DICT;
	    to->v_lock = 0;
	    if (from->vval.v_dict == NULL)
		to->vval.v_dict = NULL;
	    else if (copyID != 0 && from->vval.v_dict->dv_copyID == copyID)
	    {
		// use the copy made earlier
		to->vval.v_dict = from->vval.v_dict->dv_copydict;
		++to->vval.v_dict->dv_refcount;
	    }
	    else
		to->vval.v_dict = dict_copy(from->vval.v_dict,
							    deep, top, copyID);
	    if (to->vval.v_dict == NULL)
		ret = FAIL;
	    break;
	case VAR_UNKNOWN:
	case VAR_ANY:
	case VAR_VOID:
	    internal_error_no_abort("item_copy(UNKNOWN)");
	    ret = FAIL;
    }
    --recurse;
    return ret;
}

    void
echo_one(typval_T *rettv, int with_space, int *atstart, int *needclr)
{
    char_u	*tofree;
    char_u	numbuf[NUMBUFLEN];
    char_u	*p = echo_string(rettv, &tofree, numbuf, get_copyID());

    if (*atstart)
    {
	*atstart = FALSE;
	// Call msg_start() after eval1(), evaluating the expression
	// may cause a message to appear.
	if (with_space)
	{
	    // Mark the saved text as finishing the line, so that what
	    // follows is displayed on a new line when scrolling back
	    // at the more prompt.
	    msg_sb_eol();
	    msg_start();
	}
    }
    else if (with_space)
	msg_puts_attr(" ", echo_attr);

    if (p != NULL)
	for ( ; *p != NUL && !got_int; ++p)
	{
	    if (*p == '\n' || *p == '\r' || *p == TAB)
	    {
		if (*p != TAB && *needclr)
		{
		    // remove any text still there from the command
		    msg_clr_eos();
		    *needclr = FALSE;
		}
		msg_putchar_attr(*p, echo_attr);
	    }
	    else
	    {
		if (has_mbyte)
		{
		    int i = (*mb_ptr2len)(p);

		    (void)msg_outtrans_len_attr(p, i, echo_attr);
		    p += i - 1;
		}
		else
		    (void)msg_outtrans_len_attr(p, 1, echo_attr);
	    }
	}
    vim_free(tofree);
}

/*
 * ":echo expr1 ..."	print each argument separated with a space, add a
 *			newline at the end.
 * ":echon expr1 ..."	print each argument plain.
 */
    void
ex_echo(exarg_T *eap)
{
    char_u	*arg = eap->arg;
    typval_T	rettv;
    char_u	*arg_start;
    int		needclr = TRUE;
    int		atstart = TRUE;
    int		did_emsg_before = did_emsg;
    int		called_emsg_before = called_emsg;
    evalarg_T	evalarg;

    fill_evalarg_from_eap(&evalarg, eap, eap->skip);

    if (eap->skip)
	++emsg_skip;
    while ((!ends_excmd2(eap->cmd, arg) || *arg == '"') && !got_int)
    {
	// If eval1() causes an error message the text from the command may
	// still need to be cleared. E.g., "echo 22,44".
	need_clr_eos = needclr;

	arg_start = arg;
	if (eval1(&arg, &rettv, &evalarg) == FAIL)
	{
	    /*
	     * Report the invalid expression unless the expression evaluation
	     * has been cancelled due to an aborting error, an interrupt, or an
	     * exception.
	     */
	    if (!aborting() && did_emsg == did_emsg_before
					  && called_emsg == called_emsg_before)
		semsg(_(e_invalid_expression_str), arg_start);
	    need_clr_eos = FALSE;
	    break;
	}
	need_clr_eos = FALSE;

	if (!eap->skip)
	{
	    if (rettv.v_type == VAR_VOID)
	    {
		semsg(_(e_expression_does_not_result_in_value_str), arg_start);
		break;
	    }
	    echo_one(&rettv, eap->cmdidx == CMD_echo, &atstart, &needclr);
	}

	clear_tv(&rettv);
	arg = skipwhite(arg);
    }
    set_nextcmd(eap, arg);
    clear_evalarg(&evalarg, eap);

    if (eap->skip)
	--emsg_skip;
    else
    {
	// remove text that may still be there from the command
	if (needclr)
	    msg_clr_eos();
	if (eap->cmdidx == CMD_echo)
	    msg_end();
    }
}

/*
 * ":echohl {name}".
 */
    void
ex_echohl(exarg_T *eap)
{
    echo_attr = syn_name2attr(eap->arg);
}

/*
 * Returns the :echo attribute
 */
    int
get_echo_attr(void)
{
    return echo_attr;
}

/*
 * ":execute expr1 ..."	execute the result of an expression.
 * ":echomsg expr1 ..."	Print a message
 * ":echowindow expr1 ..." Print a message in the messages window
 * ":echoerr expr1 ..."	Print an error
 * ":echoconsole expr1 ..." Print a message on stdout
 * Each gets spaces around each argument and a newline at the end for
 * echo commands
 */
    void
ex_execute(exarg_T *eap)
{
    char_u	*arg = eap->arg;
    typval_T	rettv;
    int		ret = OK;
    char_u	*p;
    garray_T	ga;
    int		len;
    long	start_lnum = SOURCING_LNUM;

    ga_init2(&ga, 1, 80);

    if (eap->skip)
	++emsg_skip;
    while (!ends_excmd2(eap->cmd, arg) || *arg == '"')
    {
	ret = eval1_emsg(&arg, &rettv, eap);
	if (ret == FAIL)
	    break;

	if (!eap->skip)
	{
	    char_u   buf[NUMBUFLEN];

	    if (eap->cmdidx == CMD_execute)
	    {
		if (rettv.v_type == VAR_CHANNEL || rettv.v_type == VAR_JOB)
		{
		    semsg(_(e_using_invalid_value_as_string_str),
						  vartype_name(rettv.v_type));
		    p = NULL;
		}
		else
		    p = tv_get_string_buf(&rettv, buf);
	    }
	    else
		p = tv_stringify(&rettv, buf);
	    if (p == NULL)
	    {
		clear_tv(&rettv);
		ret = FAIL;
		break;
	    }
	    len = (int)STRLEN(p);
	    if (ga_grow(&ga, len + 2) == FAIL)
	    {
		clear_tv(&rettv);
		ret = FAIL;
		break;
	    }
	    if (ga.ga_len)
		((char_u *)(ga.ga_data))[ga.ga_len++] = ' ';
	    STRCPY((char_u *)(ga.ga_data) + ga.ga_len, p);
	    ga.ga_len += len;
	}

	clear_tv(&rettv);
	arg = skipwhite(arg);
    }

    if (ret != FAIL && ga.ga_data != NULL)
    {
	// use the first line of continuation lines for messages
	SOURCING_LNUM = start_lnum;

	if (eap->cmdidx == CMD_echomsg
		|| eap->cmdidx == CMD_echowindow
		|| eap->cmdidx == CMD_echoerr)
	{
	    // Mark the already saved text as finishing the line, so that what
	    // follows is displayed on a new line when scrolling back at the
	    // more prompt.
	    msg_sb_eol();
	}

	if (eap->cmdidx == CMD_echomsg)
	{
	    msg_attr(ga.ga_data, echo_attr);
	    out_flush();
	}
	else if (eap->cmdidx == CMD_echowindow)
	{
#ifdef HAS_MESSAGE_WINDOW
	    start_echowindow(eap->addr_count > 0 ? eap->line2 : 0);
#endif
	    msg_attr(ga.ga_data, echo_attr);
#ifdef HAS_MESSAGE_WINDOW
	    end_echowindow();
#endif
	}
	else if (eap->cmdidx == CMD_echoconsole)
	{
	    ui_write(ga.ga_data, (int)STRLEN(ga.ga_data), TRUE);
	    ui_write((char_u *)"\r\n", 2, TRUE);
	}
	else if (eap->cmdidx == CMD_echoerr)
	{
	    int		save_did_emsg = did_emsg;

	    // We don't want to abort following commands, restore did_emsg.
	    emsg(ga.ga_data);
	    if (!force_abort)
		did_emsg = save_did_emsg;
	}
	else if (eap->cmdidx == CMD_execute)
	{
	    int save_sticky_cmdmod_flags = sticky_cmdmod_flags;

	    // "legacy exe cmd" and "vim9cmd exe cmd" applies to "cmd".
	    sticky_cmdmod_flags = cmdmod.cmod_flags
						& (CMOD_LEGACY | CMOD_VIM9CMD);
	    do_cmdline((char_u *)ga.ga_data,
		       eap->getline, eap->cookie, DOCMD_NOWAIT|DOCMD_VERBOSE);
	    sticky_cmdmod_flags = save_sticky_cmdmod_flags;
	}
    }

    ga_clear(&ga);

    if (eap->skip)
	--emsg_skip;
    set_nextcmd(eap, arg);
}

/*
 * Skip over the name of an option: "&option", "&g:option" or "&l:option".
 * "arg" points to the "&" or '+' when called, to "option" when returning.
 * Returns NULL when no option name found.  Otherwise pointer to the char
 * after the option name.
 */
    char_u *
find_option_end(char_u **arg, int *scope)
{
    char_u	*p = *arg;

    ++p;
    if (*p == 'g' && p[1] == ':')
    {
	*scope = OPT_GLOBAL;
	p += 2;
    }
    else if (*p == 'l' && p[1] == ':')
    {
	*scope = OPT_LOCAL;
	p += 2;
    }
    else
	*scope = 0;

    if (!ASCII_ISALPHA(*p))
	return NULL;
    *arg = p;

    if (p[0] == 't' && p[1] == '_' && p[2] != NUL && p[3] != NUL)
	p += 4;	    // termcap option
    else
	while (ASCII_ISALPHA(*p))
	    ++p;
    return p;
}

/*
 * Display script name where an item was last set.
 * Should only be invoked when 'verbose' is non-zero.
 */
    void
last_set_msg(sctx_T script_ctx)
{
    char_u *p;

    if (script_ctx.sc_sid == 0)
	return;

    p = home_replace_save(NULL, get_scriptname(script_ctx.sc_sid));
    if (p == NULL)
	return;

    verbose_enter();
    msg_puts(_("\n\tLast set from "));
    msg_puts((char *)p);
    if (script_ctx.sc_lnum > 0)
    {
	msg_puts(_(line_msg));
	msg_outnum((long)script_ctx.sc_lnum);
    }
    verbose_leave();
    vim_free(p);
}

#endif // FEAT_EVAL

/*
 * Perform a substitution on "str" with pattern "pat" and substitute "sub".
 * When "sub" is NULL "expr" is used, must be a VAR_FUNC or VAR_PARTIAL.
 * "flags" can be "g" to do a global substitute.
 * Returns an allocated string, NULL for error.
 */
    char_u *
do_string_sub(
    char_u	*str,
    char_u	*pat,
    char_u	*sub,
    typval_T	*expr,
    char_u	*flags)
{
    int		sublen;
    regmatch_T	regmatch;
    int		i;
    int		do_all;
    char_u	*tail;
    char_u	*end;
    garray_T	ga;
    char_u	*ret;
    char_u	*save_cpo;
    char_u	*zero_width = NULL;

    // Make 'cpoptions' empty, so that the 'l' flag doesn't work here
    save_cpo = p_cpo;
    p_cpo = empty_option;

    ga_init2(&ga, 1, 200);

    do_all = (flags[0] == 'g');

    regmatch.rm_ic = p_ic;
    regmatch.regprog = vim_regcomp(pat, RE_MAGIC + RE_STRING);
    if (regmatch.regprog != NULL)
    {
	tail = str;
	end = str + STRLEN(str);
	while (vim_regexec_nl(&regmatch, str, (colnr_T)(tail - str)))
	{
	    // Skip empty match except for first match.
	    if (regmatch.startp[0] == regmatch.endp[0])
	    {
		if (zero_width == regmatch.startp[0])
		{
		    // avoid getting stuck on a match with an empty string
		    i = mb_ptr2len(tail);
		    mch_memmove((char_u *)ga.ga_data + ga.ga_len, tail,
								   (size_t)i);
		    ga.ga_len += i;
		    tail += i;
		    continue;
		}
		zero_width = regmatch.startp[0];
	    }

	    /*
	     * Get some space for a temporary buffer to do the substitution
	     * into.  It will contain:
	     * - The text up to where the match is.
	     * - The substituted text.
	     * - The text after the match.
	     */
	    sublen = vim_regsub(&regmatch, sub, expr, tail, 0, REGSUB_MAGIC);
	    if (sublen <= 0)
	    {
		ga_clear(&ga);
		break;
	    }
	    if (ga_grow(&ga, (int)((end - tail) + sublen -
			    (regmatch.endp[0] - regmatch.startp[0]))) == FAIL)
	    {
		ga_clear(&ga);
		break;
	    }

	    // copy the text up to where the match is
	    i = (int)(regmatch.startp[0] - tail);
	    mch_memmove((char_u *)ga.ga_data + ga.ga_len, tail, (size_t)i);
	    // add the substituted text
	    (void)vim_regsub(&regmatch, sub, expr,
				  (char_u *)ga.ga_data + ga.ga_len + i, sublen,
				  REGSUB_COPY | REGSUB_MAGIC);
	    ga.ga_len += i + sublen - 1;
	    tail = regmatch.endp[0];
	    if (*tail == NUL)
		break;
	    if (!do_all)
		break;
	}

	if (ga.ga_data != NULL)
	    STRCPY((char *)ga.ga_data + ga.ga_len, tail);

	vim_regfree(regmatch.regprog);
    }

    ret = vim_strsave(ga.ga_data == NULL ? str : (char_u *)ga.ga_data);
    ga_clear(&ga);
    if (p_cpo == empty_option)
	p_cpo = save_cpo;
    else
    {
	// Darn, evaluating {sub} expression or {expr} changed the value.
	// If it's still empty it was changed and restored, need to restore in
	// the complicated way.
	if (*p_cpo == NUL)
	    set_option_value_give_err((char_u *)"cpo", 0L, save_cpo, 0);
	free_string_option(save_cpo);
    }

    return ret;
}