Insert a single character

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created 2002 · complexity basic · author Mikko Pulkkinen · version 6.0

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Using insert mode to insert a single character feels clumsy because three key presses are needed to insert one character. Here is a slightly easier way:

:nnoremap <Space> i_<Esc>r

Now, when in normal mode, press Space followed by the character that you want to insert.

Bug: Repeating the insertion with . does not work.

Comments

I use:

:nnoremap ,i i_<Esc>r
:nnoremap ,a a_<Esc>r

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I consider this a better solution:

:nnoremap s :exec "normal i".nr2char(getchar())."\e"<CR>
:nnoremap S :exec "normal a".nr2char(getchar())."\e"<CR>

Such inserts can be repeated with '.' thus making this command worthy (it's not a big problem to make an additional keypress but imagine you need to manually put some spaces or other separators).

's' and 'S' were chosen because:

• They remind of 'single'.
• If they are used occasionally, one can use synonyms 'cl' and 'cc' instead.

What is the "\e" for?

It might be meant to represent <Escape> although in Vim 7.2 this method does not need to force an escape from insert mode.

The built-in s command is very useful, but that's a choice for the user. JohnBeckett 22:56, 15 June 2009 (UTC)

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I quite like the solution you proposed, but it does not allow for repetitions, I found myself wanting to do '5s '. I couldn't use the repetition inline because it would repeat the call to getchar so I added a simple proxy function, the result is:

function! RepeatChar(char, count)
  return repeat(a:char, a:count)
endfunction
nnoremap s :<C-U>exec "normal i".RepeatChar(nr2char(getchar()), v:count1)<CR>
nnoremap S :<C-U>exec "normal a".RepeatChar(nr2char(getchar()), v:count1)<CR>

Note that the C-U is necessary to support the ranges and as far as I could tell the '."\e"' was unnecessary, so I removed it

Interesting, thanks. Why wouldn't repeat(getchar(), v:count1) work (why the RepeatChar function)? JohnBeckett 11:20, September 28, 2010 (UTC)

Because if you use repeat(nr2char(getchar()), v:count1) it executes the "nr2char(getchar())", "v:count1" times, meaning it will try to get "v:count1" keypresses. When you pass it as a parameter to a function it is evaluated only once and the result is repeated. 12:44, September 20, 2010 (UTC)

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This is what I am using for a similar purpose. The only difference is, if a character is not provided promptly, it inserts a space:

function! InsertSingle()
  sleep 120m|let l:a = getchar(0)
  if l:a != 0
    silent! exec "normal a" . nr2char(l:a)
  else
    silent! exec "normal a "
  endif
endfunction
nnoremap <silent> <Space> :call InsertSingle()<CR>

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