use std::pin::Pin; use futures::{future, stream}; use juniper::graphql_subscription; type Stream<'a, I> = Pin + Send + 'a>>; struct ObjA; #[graphql_subscription] impl ObjA { async fn wrong( &self, #[graphql(default = [true, false, false])] input: [bool; 2], ) -> Stream<'static, bool> { Box::pin(stream::once(future::ready(input[0]))) } } fn main() {}