问题
It appears from the :help while documentation that :
NOTE: The ":append" and ":insert" commands don't work
properly inside a ":while" and ":for" loop.
And I can confirm they don't. But what should I use then to insert text from inside a loop?
回答1:
The :insert and :append commands are mostly meant for interactive use. In a Vimscript, you can instead use the lower-level setline() and append() functions, which do work well in a loop. (They are also easier to use, because you can directly pass a List of lines to them.)
来源：https://stackoverflow.com/questions/28511027/how-to-insert-text-from-inside-a-vimscript-loop