usecomposable_utils::AsyncOptionExt;
async fndouble(value:usize)->usize{
value *2}#[test]fnasync_map(){async_io::block_on(async {let value =Some(69);let value = value
.async_map(|v|async move{double(v).await }).await
.unwrap_or_else(||panic!("value should always be Some"));assert_eq!(value,138);});}