Vim 80 column layout concerns

coding-stylevim

The way I do 80-column indication in Vim seems incorrect:set columns=80.
At times I also set textwidth, but I want to be able to see and anticipate line overflow with the set columns alternative.

This has some unfortunate side effects:

I can't set number for fear of splitting between files that have different orders of line numbers; i.e. < 100 line files and >= 100 line files will require two different set columns values because of the extra column used for the additional digit display.
I also start new (g)Vim sessions instead of splitting windows vertically. This is because vsplit forces me to set columns every time I open or close a pane, so starting a new session is less hassle.

How do you handle the 80-character indication when you want to set numbers, vertically split, etc.?

Best Answer

As of vim 7.3, you can use set colorcolumn=80 (set cc=80 for short).

Since earlier versions do not support this, my .vimrc uses instead:

if exists('+colorcolumn')
  set colorcolumn=80
else
  au BufWinEnter * let w:m2=matchadd('ErrorMsg', '\%>80v.\+', -1)
endif

Use `\r` instead of `\n`.

Substituting by \n inserts a null character into the text. To get a newline, use \r. When searching for a newline, you’d still use \n, however. This asymmetry is due to the fact that \n and \r do slightly different things:

\n matches an end of line (newline), whereas \r matches a carriage return. On the other hand, in substitutions \n inserts a null character whereas \r inserts a newline (more precisely, it’s treated as the input CR). Here’s a small, non-interactive example to illustrate this, using the Vim command line feature (in other words, you can copy and paste the following into a terminal to run it). xxd shows a hexdump of the resulting file.

echo bar > test
(echo 'Before:'; xxd test) > output.txt
vim test '+s/b/\n/' '+s/a/\r/' +wq
(echo 'After:'; xxd test) >> output.txt
more output.txt

Before:
0000000: 6261 720a                                bar.
After:
0000000: 000a 720a                                ..r.

In other words, \n has inserted the byte 0x00 into the text; \r has inserted the byte 0x0a.

Best Answer

Related Solutions

How to effectively work with multiple files in Vim

How to replace a character by a newline in Vim

Use \r instead of \n.

Related Topic

Use `\r` instead of `\n`.