syntax_data: {"ast_node_type":"other","tokens":[{"end":70,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // Look up the type in the args. It really should be in there.
context_before:     fn ty_for_param(&self, p: I::ParamTy, source_ty: I::Ty) -> I::Ty {
context_after:         let opt_ty = self.args.get(p.index() as usize).map(|arg| arg.kind());