Indenting XML and HTML from vim

vim has an awesome feature, using which you can pipe a range through an external command. This is pretty useful if you're opening up an un-indented or poorly-indented XML or HTML file. If you want to indent your entire file, simply do the following:

:%!tidy -i -xml -q

The -i option tells tidy that it needs to indent the content, -xml tells tidy that the content is well-formed XML, and -q puts tidy into "quiet mode" where extraneous information is suppressed. You can also specify ranges like so:

:40, 74!tidy -i -xml -q

This indents content between lines 40 and 74 (both lines inclusive). You can also do:

:., .+50!tidy -i -xml -q

This indents the current line and the next 50 lines. You can also do the same for HTML:

:%!tidy -i -xml -q

You can of course, supply additional parameters to tidy to customize the indenting.

:%!tidy -i -q