[SOLVED] vimscript: how delete a variable number of lines

porphyry5 · 09-09-2013, 05:31 PM

In a vimscript I need to repeatedly delete lines from the buffer, but the number of lines to delete will vary with each iteration of the loop.
:d is the only command I know of that will remove entire lines, but how can I use it with a variable specifying the number of lines to be deleted?

TobiSGD · 09-09-2013, 06:31 PM

You can do it with a loop, like this:

Code:

:let linesToRemove =3
:while linesToRemove > 0
:  d
:  let linesToRemove -=1
:endwhile

porphyry5 · 09-09-2013, 06:48 PM

Quote:

Originally Posted by TobiSGD

You can do it with a loop, like this:

Code:

:let linesToRemove =3
:while linesToRemove > 0
:  d
:  let linesToRemove -=1
:endwhile

Many thanks. I also did it by setting marks and deleting between the marks, i.e

Code:

    :normal ma  
    :call cursor(lno, 1)  
    :normal mb  
    :'a,'bd

where lno is the line number of the last line of the group to be deleted

TobiSGD · 09-09-2013, 07:53 PM

Looks more elegant than a loop, definitely, but it may be not a good idea to change marks, especially when you deploy your script to other users. I thought about that and with a little reading in the Vim documentation I found this way to do it:

Code:

"Get the line number of the current cursor position
"for info on that look at http://vimdoc.sourceforge.net/htmldoc/eval.html#line()
:let cLine = line(".")

"Since in your case lno already contains the number of the last line 
"in the block more math is not necessary, of course any kind of arithmetic
"to determine the last line can be done here

"Okay, now we need to create the command to delete the block and execute it
"More info: http://www.cs.csubak.edu/docs/vim/eval.html#:execute
:execute cLine . "," . lno . "d"

"For some reason you can't execute the command directly like
":cLine,lnod
"This will throw an error E488

This solution looks more complicated, but will not touch marks (that are possibly already set by the user).