How to comment out HTML/XML element in VIM?

You can use a combination of matching XML tags, as can be seen in this question and Perl's search and replace.

For instance, given this snippet:

<TypeDef name="a">  <ArrayType high="14" low="0">    <UndefType type="node">    </UndefType>  </ArrayType></TypeDef>

Put the cursor on either the opening or closing TypeDef and type the following sequence:

vat:s/^\(.*\)$/<!-- \1 -->/

1. v - puts you into visual mode
2. at - selects the whole XML tag
3. :s/^\(.*\)$/<!-- \1 -->/ - surrounds each line with '<!-- ... -->', the comment delimiters for XML

Alternatively, you can just delete it like this:

dat

1. d - delete according to the following movements
2. at - as before

To delete id use then use vat:s/-->// to delete comments

I use the tComment plugin. You can find a detailed video tutorial here on how to install and use it.

The plugin is very useful as it allows you to toggle comments from both the command and input interface, and you can do so using both visual mode and motions (like gcw, or gc3w)

If you use emmet-vim, you can select the whole contents of the tag you would like to comment out by pressing v a t and then press Ctrl y /