syntax_data: {"ast_node_type":"function","tokens":[{"end":38,"kind":"keyword","start":0,"text":"fn"}]}
source_snippet:     fn clone_opaque_types_added_since(
context_before:     ) -> Vec<(ty::OpaqueTypeKey<Self::Interner>, <Self::Interner as Interner>::Ty)>;
context_after:         &self,