syntax_data: {"ast_node_type":"variable","tokens":[{"end":55,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:     let args = tcx.mk_args(&[ref_coroutine_ty.into()]);
context_before:     let pin_adt_ref = tcx.adt_def(pin_did);
context_after:     let pin_ref_coroutine_ty = Ty::new_adt(tcx, pin_adt_ref, args);