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use ;
/// "Lifts" and converts an [`Unpin`] [`Stream`] into an
/// <code>impl [LendingIterator]</code> which lends futures (an `S`,
/// say).
///
/// [`Stream`]: https://docs.rs/futures/^0.3.21/futures/stream/trait.Stream.html
/// [`StreamExt`]: https://docs.rs/futures/^0.3.21/futures/stream/trait.StreamExt.html
/// [`BoxFuture`]: https://docs.rs/futures/^0.3.21/futures/future/type.BoxFuture.html
///
/** - ```rust
# ::futures::executor::block_on(async {
use {
::futures::{
prelude::*,
},
::lending_iterator::{
prelude::*,
},
};
let stream = stream::iter(1..=3);
let mut lending_iterator = lending_iterator::from_stream(stream);
loop {
if let Some(item) = lending_iterator.next().unwrap().await {
println!("Got `{}`", item);
} else {
break;
}
}
# })
``` */
///
/// This could be useful to get access to the more lifetime-powerful adapters of
/// this crate (compared to the adapters on [`StreamExt`], for instance).
///
/// - That being said, said adapters often requires the explicitly-turbofished
/// `HKT` parameter, which in turn requires **nameable types**.
///
/// Sadly, most <code>impl [Future]</code> are unnameable!. So you'll mostly
/// need to use [`BoxFuture`]s and whatnot.
///
/// For `nightly` users, however, `type_alias_impl_trait` can be leveraged
/// to avoid unnecessary [`Box`]ing. Keep it in mind!
///
/// [Future]: ::core::future::Future
/// [`Box`]: ::alloc::boxed::Box
///
/// For instance, here is what a `&mut`-based "unfold" async iterator
/// construction would look like:
///
/** - ```rust
# ::futures::executor::block_on(async {
use {
::futures::{
future::BoxFuture,
prelude::*,
},
::lending_iterator::{
prelude::*,
},
};
let mut iter =
lending_iterator::repeat_mut(0)
.map::<HKT!(BoxFuture<'_, Option<i32>>), _>(
|[], state: &mut _| async move {
if *state <= 2 {
let yielded = *state * 2;
*state += 1;
Some(yielded)
} else {
None
}
}
.boxed()
)
;
let mut result = vec![];
loop {
if let Some(item) = iter.next().unwrap().await {
result.push(item);
} else {
break;
}
}
assert_eq!(result, [0, 2, 4]);
# })
``` */
///
pub
/// The <code>impl [LendingIterator]</code> returned by [`from_stream()`].
pub
;