syntax_data: {"ast_node_type":"variable","tokens":[{"end":57,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:             let pin_args = tcx.mk_args(&[env_ty.into()]);
context_before:             let pin_adt_ref = tcx.adt_def(pin_did);
context_after:             let env_ty = match coroutine_kind {