--- a/runtime/doc/eval.txt
+++ b/runtime/doc/eval.txt
@@ -1716,7 +1716,7 @@ call( {func}, {arglist} [, {dict}])
 				any	call {func} with arguments {arglist}
 ceil( {expr})			Float	round {expr} up
 changenr()			Number	current change number
-char2nr( {expr})		Number	ASCII value of first char in {expr}
+char2nr( {expr}[, {utf8}])	Number	ASCII/UTF8 value of first char in {expr}
 cindent( {lnum})		Number	C indent for line {lnum}
 clearmatches()			none	clear all matches
 col( {expr})			Number	column nr of cursor or mark
@@ -1873,7 +1873,7 @@ mkdir( {name} [, {path} [, {prot}]])
 mode( [expr])			String	current editing mode
 mzeval( {expr})			any	evaluate |MzScheme| expression
 nextnonblank( {lnum})		Number	line nr of non-blank line >= {lnum}
-nr2char( {expr})		String	single char with ASCII value {expr}
+nr2char( {expr}[, {utf8}])	String	single char with ASCII/UTF8 value {expr}
 or( {expr}, {expr})		Number  bitwise OR
 pathshorten( {expr})		String	shorten directory names in a path
 pow( {x}, {y})			Float	{x} to the power of {y}
@@ -2294,14 +2294,16 @@ changenr()						*changenr()*
 		redo it is the number of the redone change.  After undo it is
 		one less than the number of the undone change.
 
-char2nr({expr})						*char2nr()*
+char2nr({expr}[, {utf8}])					*char2nr()*
 		Return number value of the first char in {expr}.  Examples: >
 			char2nr(" ")		returns 32
 			char2nr("ABC")		returns 65
-<		The current 'encoding' is used.  Example for "utf-8": >
+<		When {utf8} is omitted or zero, the current 'encoding' is used.
+		Example for "utf-8": >
 			char2nr("á")		returns 225
 			char2nr("á"[0])		returns 195
-<		A combining character is a separate character.
+<		With {utf8} set to 1, always treat as utf-8 characters.
+		A combining character is a separate character.
 		|nr2char()| does the opposite.
 
 cindent({lnum})						*cindent()*
@@ -4371,14 +4373,16 @@ nextnonblank({lnum})					*nextnonblank()
 		below it, zero is returned.
 		See also |prevnonblank()|.
 
-nr2char({expr})						*nr2char()*
+nr2char({expr}[, {utf8}])				*nr2char()*
 		Return a string with a single character, which has the number
 		value {expr}.  Examples: >
 			nr2char(64)		returns "@"
 			nr2char(32)		returns " "
-<		The current 'encoding' is used.  Example for "utf-8": >
+<		When {utf8} is omitted or zero, the current 'encoding' is used.
+		Example for "utf-8": >
 			nr2char(300)		returns I with bow character
-<		Note that a NUL character in the file is specified with
+<		With {utf8} set to 1, always return utf-8 characters.
+		Note that a NUL character in the file is specified with
 		nr2char(10), because NULs are represented with newline
 		characters.  nr2char(0) is a real NUL and terminates the
 		string, thus results in an empty string.