Provide parser for contracts.coffee-style syntax

[kennknowles]

I would love for the following to be equivalent to writing out the AST longhand in Javascript.

var id = c.guard( c.parse('(Num) -> Num'),
    function(x) { return x; }
);

Eliding the call to parse using reflection is presumably safe as well?

[disnet]

Yes we should definitely do this! What do you mean by reflection?

[kennknowles]

Hardly qualifies as reflection in a dynamic language... https://github.com/kennknowles/python-rightarrow/blob/master/rightarrow/enforce.py#L7

[disnet]

Oh! You mean overload guard to check if it's a contract or a string (in which case parse the string into a contract). Yeah, that'd work.

[joelmccracken]

so, what if we used the function tostring method and parsed type signature information out of it? something like:

inc = c.guard(function(x){ 
  /* (Num) -> Num */ 
  return x+1;
});

[disnet]

We've moved to using macros so I don't think we need this anymore.