html2xml

While this library doesn't cover the full gamut of possible weirdness that HTML provides, it does handle a lot of the most obvious stuff. All of the following are accounted for:

• Unclosed Tags:

  HTMLtoXML("Hello") == '
  Hello
  '

• Empty Elements:

  HTMLtoXML("") == ''

• Block vs. Inline Elements:

  HTMLtoXML("Hello John") == 'Hello 
  John
  '

• Self-closing Elements:

  HTMLtoXML("Hello
  World") == '
  Hello
  World
  '

• Attributes Without Values:

  HTMLtoXML("") == ''

Note: It does not take into account where in the document an element should exist. Right now you can put block elements in a head or th inside a p and it'll happily accept them. It's not entirely clear how the logic should work for those, but it's something that I'm open to exploring.