Call function on several lines

Question

I have a function that changes the 6th caracter of a line to a dollar symbol ($).

I want it to be performed on several lines, so I naively did a "while" loop using a counter (as shown under).

But I have the feeling that there must be a much simpler, more "vim-esque" way to do that -- my function seems a bit complicated for such a simple task. Maybe I'm wrong, but I would appreciate any simplification/comments.

My current function is :

function! DollarSplit(nlines)
   let current_pos = getpos(".")
   let a:count = 0
   while a:count < a:nlines 
      normal! 6|r$j
      a:count += 1
   endwhile
   call setpos(".", current_pos)
endfunction

Answer 1

function! DollarSplit() range
   let current_pos = getpos(".")
   execute a:firstline . "," . a:lastline . "normal! 6|r$"
   call setpos(".", current_pos)
endfunction

See :help function-range-example.

Answer 2

You can use the following replace:

function! DollarSplit(nlines)
   let current_pos = getpos(".")

   execute ',+'.a:nlines.'s/^\(.\{5}\).\(.*\)/\1$\2/g'

   call setpos(".", current_pos)
endfunction

Decomposing:

execute '      " prepare a command
,+             " the command will operate on lines from current to
'.a:nlines.'   " current+a:nlines
s/^            " the command is a substitution, starting at start of line
\(.\{5}\)      " capture the first 5 characters into a group (1)
.              " match any 6th character
\(.*\)         " capture the remaining of the line into a group (2)
/\1$\2         " replace by group 1 $ group 2
/g'            " end the substitution

This will basically create two matching group, surrounding the char you want to replace, and then restore the two groups with a $ inside.

References:

• :h ranges
• :h substitute