Explict any casting results in emitting 'undefined'

[dariajung]

Something like:

var x = <any>Some_Class; will result in an emit that looks like var x = undefined;

This is likely due to the fact that there is no specific type information associated with an any type.

This issue is related to #53.

Possible ways to approach this:

• Throw an error to the user telling them to type their program more specifically.
• Show the user a warning about using explicit any casting, and emit the object being cast as is, or unsafely rename it.