fn all<Fut, F>(self, f: F) -> All<Self, Fut, F>
    where
        F: FnMut(Self::Item) -> Fut,
        Fut: Future<Output = bool>,
        Self: Sized,
    {
        assert_future::<bool, _>(All::new(self, f))
    }
Execute predicate over asynchronous stream, and return `true` if all element in stream satisfied a predicate.

# Examples

```
# futures::executor::block_on(async {
use futures::stream::{self, StreamExt};

let number_stream = stream::iter(0..10);
let less_then_twenty = number_stream.all(|i| async move { i < 20 });
assert_eq!(less_then_twenty.await, true);
# });
```
futures-util/src/stream/stream/mod.rs