detect-is-it-html-or-xhtml npm package

This package is retired. The published package, documentation, examples, and changelog remain available.

Retirement

This package has been retired and is no longer maintained.

The API documentation below is archived. Archived examples, the changelog, and the published package on npm remain available.

It is a function which detects, does given string resemble XHTML or HTML. Practically, it affects closing slashes and singleton tags in the markup.

The main function detectIsItHTMLOrXhtml() is imported like this:

It’s a function which takes one argument:

If the input is not String type, this package will throw an error. If the input is missing completely, it will return null.

You can import version:

The algorithm is the following:

Look for doctype. If recognised, Bob’s your uncle, here’s your answer.
IF there’s no doctype or it’s messed up beyond recognition, DO scan all singleton tags (<img>, <br> and <hr>) and see which type the majority is (closed or not closed).
In a rare case when there is an equal amount of both closed and unclosed tags, lean for html.
If (there are no tags in the input) OR (there are no doctype tags and no singleton tags), return null.