syntax_data: {"ast_node_type":"other","tokens":[{"end":64,"kind":"keyword","start":0,"text":"defining_opaque_types_and_generators:"}]}
source_snippet:         defining_opaque_types_and_generators: ty::List::empty(),
context_before:     let infcx = tcx.infer_ctxt().build(ty::TypingMode::Analysis {
context_after:     });