syntax_data: {"ast_node_type":"other","tokens":[{"end":51,"kind":"keyword","start":0,"text":"Ty::new_closure(tcx,"}]}
source_snippet:                 Ty::new_closure(tcx, def_id, args),
context_before:             let env_ty = tcx.closure_env_ty(
context_after:                 args.as_closure().kind(),