syntax_data: {"ast_node_type":"other","tokens":[{"end":59,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:                     // erased_self_ty : 'a` (we interpret a
context_before:                     // : 'a`, but be wary of something like `for<'a>
context_after:                     // higher-ranked bound like that as 'static,