syntax_data: {"ast_node_type":"variable","tokens":[{"end":96,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:         let TraitImpls { blanket_impls, non_blanket_impls } = self.trait_impls_of(trait_def_id);
context_before:     pub fn all_impls(self, trait_def_id: DefId) -> impl Iterator<Item = DefId> {