syntax_data: {"ast_node_type":"other","tokens":[{"end":60,"kind":"keyword","start":0,"text":"///"}]}
source_snippet: /// (which would be represented by the type `PolyTraitRef ==
context_before: /// compiler's representation for things like `for<'a> Fn(&'a isize)`
context_after: /// Binder<I, TraitRef>`). Note that when we instantiate,