Replace sample with a hidden from_iter implementation for double-ended-stream

Author: felipesere

src/stream/double_ended/from_iter.rs

@@ -0,0 +1,38 @@
+use crate::stream::Stream;
+
+use std::pin::Pin;
+use std::task::{Context, Poll};
+use crate::stream::DoubleEndedStream;
+
+/// A double-ended stream that was created from iterator.
+///
+/// This stream is created by the [`from_iter`] function.
+/// See it documentation for more.
+///
+/// [`from_iter`]: fn.from_iter.html
+#[derive(Debug)]
+pub struct FromIter<T> {
+    inner: Vec<T>,
+}
+
+pub fn from_iter<I: IntoIterator>(iter: I) -> FromIter<I::Item> {
+    FromIter { inner: iter.into_iter().collect() }
+}
+
+impl<T> Unpin for FromIter<T> {}
+
+impl<T> Stream for FromIter<T> {
+    type Item = T;
+    fn poll_next(mut self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
+        if self.inner.len() > 0 {
+            return Poll::Ready(Some(self.inner.remove(0)));
+        }
+        return Poll::Ready(None);
+    }
+}
+
+impl<T> DoubleEndedStream for FromIter<T> {
+    fn poll_next_back(mut self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
+        Poll::Ready(self.inner.pop())
+    }
+}

src/stream/double_ended/mod.rs

@@ -3,12 +3,14 @@ mod nth_back;
 mod rfind;
 mod rfold;
 mod try_rfold;
+mod from_iter;
 
 use next_back::NextBackFuture;
 use nth_back::NthBackFuture;
 use rfind::RFindFuture;
 use rfold::RFoldFuture;
 use try_rfold::TryRFoldFuture;
+pub use from_iter::{from_iter, FromIter};
 
 extension_trait! {
     use crate::stream::Stream;
@@ -113,10 +115,9 @@ extension_trait! {
             ```
             # fn main() { async_std::task::block_on(async {
             #
-            use async_std::stream::Sample;
-            use async_std::stream::double_ended::DoubleEndedStreamExt;
+            use async_std::stream::double_ended::{self, DoubleEndedStreamExt};
 
-            let mut s = Sample::from(vec![7u8]);
+            let mut s = double_ended::from_iter(vec![7u8]);
 
             assert_eq!(s.next_back().await, Some(7));
             assert_eq!(s.next_back().await, None);
@@ -141,10 +142,9 @@ extension_trait! {
             ```
             # fn main() { async_std::task::block_on(async {
             #
-            use async_std::stream::Sample;
-            use async_std::stream::double_ended::DoubleEndedStreamExt;
+            use async_std::stream::double_ended::{self, DoubleEndedStreamExt};
 
-            let mut s = Sample::from(vec![1u8, 2, 3, 4, 5]);
+            let mut s = double_ended::from_iter(vec![1u8, 2, 3, 4, 5]);
 
             let second = s.nth_back(1).await;
             assert_eq!(second, Some(4));
@@ -172,10 +172,9 @@ extension_trait! {
             ```
             # fn main() { async_std::task::block_on(async {
             #
-            use async_std::stream::Sample;
-            use async_std::stream::double_ended::DoubleEndedStreamExt;
+            use async_std::stream::double_ended::{self, DoubleEndedStreamExt};
 
-            let mut s = Sample::from(vec![1u8, 2, 3, 4, 5]);
+            let mut s = double_ended::from_iter(vec![1u8, 2, 3, 4, 5]);
 
             let second = s.rfind(|v| v % 2 == 0).await;
             assert_eq!(second, Some(4));
@@ -202,10 +201,9 @@ extension_trait! {
             ```
             # fn main() { async_std::task::block_on(async {
             #
-            use async_std::stream::Sample;
-            use async_std::stream::double_ended::DoubleEndedStreamExt;
+            use async_std::stream::double_ended::{self, DoubleEndedStreamExt};
 
-            let s = Sample::from(vec![1, 2, 3, 4, 5]);
+            let s = double_ended::from_iter(vec![1u8, 2, 3, 4, 5]);
 
             let second = s.rfold(0, |acc, v| v + acc).await;
 
@@ -237,10 +235,9 @@ extension_trait! {
             ```
             # fn main() { async_std::task::block_on(async {
             #
-            use async_std::stream::Sample;
-            use async_std::stream::double_ended::DoubleEndedStreamExt;
+            use async_std::stream::double_ended::{self, DoubleEndedStreamExt};
 
-            let s = Sample::from(vec![1, 2, 3, 4, 5]);
+            let s = double_ended::from_iter(vec![1u8, 2, 3, 4, 5]);
             let sum = s.try_rfold(0, |acc, v| {
                 if (acc+v) % 2 == 1 {
                     Ok(v+3)

src/stream/mod.rs

@@ -307,7 +307,6 @@ pub use once::{once, Once};
 pub use repeat::{repeat, Repeat};
 pub use repeat_with::{repeat_with, RepeatWith};
 pub use stream::*;
-pub use crate::stream::sample::Sample;
 
 pub mod stream;
 
@@ -317,7 +316,6 @@ mod from_iter;
 mod once;
 mod repeat;
 mod repeat_with;
-mod sample;
 
 cfg_unstable! {
     pub mod double_ended;