Expression closures - use-cases for shortcut lambda syntax(blocks)

[Jeff Dyer]

> There's no hard or fast rule here. Aesthetics matter, but usability
> should trump if in conflict. Alas we don't have much usability data.
> I'll try to get some based on JS1.7.

Great! And my sense of aesthetics might change in the mean time :)

While we are talking about function expressions. I assume that type
parameters are allowed. For example,

   var id = .<t>(x:t):t=>x

should work. It falls out naturally as the syntax on the left of => is a
FunctionSignature. Can't remember, maybe we already talked about this.

Jd