Looks pretty good to me. With a couple of changes this should be good to go in. I'd like @ahejlsberg to weigh in if we want to go ahead with them.

My only concern is how this affects our ability to do something like add support for #pp-directives in the future. Or maybe that wouldn't be a problem as we'd still just detect #! as a special directive.

Done:

• add tests where the #! isn't on the first position
• CR based cleanup

@mhegazy You ok with this?

Done (as an amendment on the CR commit):

• const for regex
• further cleanup on code indentation

thanks!