syntax_data: {"ast_node_type":"other","tokens":[{"end":75,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // under the same binders as `Foo`. Currently, this doesn't matter,
context_before:         // `dyn for<'a> Foo<'a, Bar = &'a ()> + Send`. In this case, `Send` is
context_after:         // because only *auto traits* are allowed other than the principal trait