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Tip 1343 • Previous Tip • Next Tip

Created: September 26, 2006 Complexity: intermediate Author: Michael Hooreman Minimum version: n/a Karma: 68/38 Imported from: Tip#1343

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If you are already in Vim, there are two methods to do a vimdiff:

• Run another Vim with command line vimdiff.
• Open a new window (C-w s) and then enter appropriate commands in the two buffers.

This tip provides a function (SetDiffEnviron) to set the "diff" environment in buffer. So, if you want to diff the right and the left window, you have to run :SetDiffEnviron into the right and the left buffer.

Add the following to your vimrc file:

function! SetDiffEnviron()
  set diff
  set scrollbind
  set scrollopt=ver,jump,hor
  set nowrap
  set fdm=diff
endfunction
:command! SetDiffEnviron call SetDiffEnviron()

[edit] References

• :help :diffthis
• :help :diffoff

[edit] Comments

How does this differ from the :diffthis command?

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Might I suggest the following commands instead:

:sp <filename>
:windo diffthis

For variety, you could try :vs instead of :sp

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I think the easiest way to diff a currently open file with another is the :diffsplit command. It loads the file and sets all the right options. Personally I like to use :vert diffsplit

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Getting into 'diff' mode is quite easy, as other comments have shown. Turning off 'diff' mode (without quitting Vim or deleting the buffers) is more complex. I use the following function:

" Switch off diff-mode of all currently open windows.
command! DiffOff call DiffOff()
function! DiffOff()
  windo set nodiff
  windo set noscrollbind
  " Reset, then restore the 'foldmethod' and 'foldcolumn' settings by
  " re-setting the filetype. This triggers the filetype-based folding to be
  " reactivated, and ( contrary to a simple :e!) works even on modified
  " buffers.
  windo set foldmethod=manual
  windo set foldcolumn=0
  windo unlet! b:did_ftplugin | let &filetype = &filetype
endfunction

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As of Vim 7, there is also :diffoff which is very similar to the DiffOff function above.

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