syntax_data: {"ast_node_type":"other","tokens":[{"end":71,"kind":"keyword","start":0,"text":"//!"}]}
source_snippet: //! refers to rules defined in RFC 1214 (`OutlivesFooBar`), so see that
context_before: //! The outlives relation `T: 'a` or `'a: 'b`. This code frequently
context_after: //! RFC for reference.