{"ast_node_type":"other","tokens":[{"end":67,"kind":"keyword","start":0,"text":"ecx.eq(goal.param_env,"}]}
            ecx.eq(goal.param_env, wrapped_expected_ty, yield_ty)?;
            let yield_ty = args.as_coroutine().yield_ty();
            ecx.instantiate_normalizes_to_term(goal, expected_ty.into());