What are the dark corners of Vim your mom never told you about? [closed]

Answer 1

I just found this one today via NSFAQ:

Comment blocks of code.

Enter Blockwise Visual mode by hitting CTRL-V.

Mark the block you wish to comment.

Hit I (capital I) and enter your comment string at the beginning of the line. (// for C++)

Hit ESC and all lines selected will have // prepended to the front of the line.

Answer 2

:! [command] executes an external command while you're in Vim.

But add a dot after the colon, :.! [command], and it'll dump the output of the command into your current window. That's : . !

For example:

:.! ls

I use this a lot for things like adding the current date into a document I'm typing:

:.! date

Answer 3

Macros can call other macros, and can also call itself.

eg:

qq0dwj@qq@q

...will delete the first word from every line until the end of the file.

This is quite a simple example but it demonstrates a very powerful feature of vim

Answer 4

Sometimes a setting in your .vimrc will get overridden by a plugin or autocommand. To debug this a useful trick is to use the :verbose command in conjunction with :set. For example, to figure out where cindent got set/unset:

:verbose set cindent?

This will output something like:

cindent
    Last set from /usr/share/vim/vim71/indent/c.vim

This also works with maps and highlights. (Thanks joeytwiddle for pointing this out.) For example:

:verbose nmap U
n  U             <C-R>
        Last set from ~/.vimrc

:verbose highlight Normal
Normal         xxx guifg=#ffffdffffd guibg=#111111 font=Inconsolata Medium 14
        Last set from ~/src/vim-holodark/colors/holodark.vim

Answer 5

Often, I like changing current directories while editing - so I have to specify paths less.

cd %:h

Answer 6

:%!xxd

Make vim into a hex editor.

:%!xxd -r

Revert.

Warning: If you don't edit with binary (-b), you might damage the file. – Josh Lee in the comments.