[there]

seems to me that if they went to the trouble to make it understand xml syntax and error out on invalid code, they should have just made it auto-close tags. on pages where there are heavily nested divs and other things, auto-closing the tags would make the code smaller while still generating valid xhtml and not bothering the developer with such trivial things.

     echo <div><strong><em>blah;

[andre]

One last feature of XHP, which has been invaluable to us at Facebook, is that you can define your own elements which can condense a complex component into a simple XHP tag. XHP has a rich collection of declarations which let you define new elements, configure their expected attributes, as well as describe their content model.

[Maascamp]

While I understand where you're coming from, I feel like that would result in incredibly confusing markup and only lead to increased headaches down the road. I'm glad they left that out.