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-rw-r--r--third_party/rust/futures-0.1.31/src/stream/skip.rs84
1 files changed, 84 insertions, 0 deletions
diff --git a/third_party/rust/futures-0.1.31/src/stream/skip.rs b/third_party/rust/futures-0.1.31/src/stream/skip.rs
new file mode 100644
index 0000000000..a1d7b49797
--- /dev/null
+++ b/third_party/rust/futures-0.1.31/src/stream/skip.rs
@@ -0,0 +1,84 @@
+use {Poll, Async};
+use stream::Stream;
+
+/// A stream combinator which skips a number of elements before continuing.
+///
+/// This structure is produced by the `Stream::skip` method.
+#[derive(Debug)]
+#[must_use = "streams do nothing unless polled"]
+pub struct Skip<S> {
+ stream: S,
+ remaining: u64,
+}
+
+pub fn new<S>(s: S, amt: u64) -> Skip<S>
+ where S: Stream,
+{
+ Skip {
+ stream: s,
+ remaining: amt,
+ }
+}
+
+impl<S> Skip<S> {
+ /// Acquires a reference to the underlying stream that this combinator is
+ /// pulling from.
+ pub fn get_ref(&self) -> &S {
+ &self.stream
+ }
+
+ /// Acquires a mutable reference to the underlying stream that this
+ /// combinator is pulling from.
+ ///
+ /// Note that care must be taken to avoid tampering with the state of the
+ /// stream which may otherwise confuse this combinator.
+ pub fn get_mut(&mut self) -> &mut S {
+ &mut self.stream
+ }
+
+ /// Consumes this combinator, returning the underlying stream.
+ ///
+ /// Note that this may discard intermediate state of this combinator, so
+ /// care should be taken to avoid losing resources when this is called.
+ pub fn into_inner(self) -> S {
+ self.stream
+ }
+}
+
+// Forwarding impl of Sink from the underlying stream
+impl<S> ::sink::Sink for Skip<S>
+ where S: ::sink::Sink
+{
+ type SinkItem = S::SinkItem;
+ type SinkError = S::SinkError;
+
+ fn start_send(&mut self, item: S::SinkItem) -> ::StartSend<S::SinkItem, S::SinkError> {
+ self.stream.start_send(item)
+ }
+
+ fn poll_complete(&mut self) -> Poll<(), S::SinkError> {
+ self.stream.poll_complete()
+ }
+
+ fn close(&mut self) -> Poll<(), S::SinkError> {
+ self.stream.close()
+ }
+}
+
+impl<S> Stream for Skip<S>
+ where S: Stream,
+{
+ type Item = S::Item;
+ type Error = S::Error;
+
+ fn poll(&mut self) -> Poll<Option<S::Item>, S::Error> {
+ while self.remaining > 0 {
+ match try_ready!(self.stream.poll()) {
+ Some(_) => self.remaining -= 1,
+ None => return Ok(Async::Ready(None)),
+ }
+ }
+
+ self.stream.poll()
+ }
+}