patch 8.2.4552: in a :def function "put = expr" does not work Commit: https://github.com/vim/vim/commit/d0b7bfa95798f5ec743d8afffbffb83aeac823da Author: Bram Moolenaar <Bram@vim.org> Date: Sat Mar 12 14:51:16 2022 +0000 patch 8.2.4552: in a :def function "put = expr" does not work Problem: In a :def function "put = expr" does not work. Solution: Skip over white space. (closes https://github.com/vim/vim/issues/9936)

" Script to fill the window with emoji characters, one per line.
" Source this script: :source %

if &modified
  new
else
  enew
endif

" Use a compiled Vim9 function for speed
def DoIt()
  var lnum = 1
  for c in range(0x100, 0x1ffff)
    var cs = nr2char(c)
    if charclass(cs) == 3
      setline(lnum, '|' .. cs .. '| ' .. strwidth(cs))
      lnum += 1
    endif
  endfor
enddef

call DoIt()
set nomodified