andrew blinn

Here's an (initially) single line version of this:   

hmm.. would need to decide what the error should be. the example shown doesn't seem fatally problematic, in that even if someone believed X gets bound by the let, it...

probably just an arity error for constructors in patterns would do it?

not sure we need any more information. we know constructor arities from types in ctx. so: 1. for pattern ap statics, check if fun pos is constructor with arrow type....