syntax_data: {"ast_node_type":"other","tokens":[{"end":72,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // all `'a`, then we must know that `T:Bar<'a,'a>` holds for all
context_before:         // holds. So if there is an impl of `T:Foo<'a>` that applies to
context_after:         // `'a`.