pub struct Lines<R> { /* private fields */ }
io-util
only.Expand description
Reads lines from an AsyncBufRead
.
A Lines
can be turned into a Stream
with LinesStream
.
This type is usually created using the lines
method.
Implementations
Returns the next line in the stream.
Cancel safety
This method is cancellation safe.
Examples
use tokio::io::AsyncBufReadExt;
let mut lines = my_buf_read.lines();
while let Some(line) = lines.next_line().await? {
println!("length = {}", line.len())
}
Unwraps this Lines<R>
, returning the underlying reader.
Note that any leftover data in the internal buffer is lost. Therefore, a following read from the underlying reader may lead to data loss.
Polls for the next line in the stream.
This method returns:
Poll::Pending
if the next line is not yet available.Poll::Ready(Ok(Some(line)))
if the next line is available.Poll::Ready(Ok(None))
if there are no more lines in this stream.Poll::Ready(Err(err))
if an IO error occurred while reading the next line.
When the method returns Poll::Pending
, the Waker
in the provided
Context
is scheduled to receive a wakeup when more bytes become
available on the underlying IO resource. Note that on multiple calls to
poll_next_line
, only the Waker
from the Context
passed to the most
recent call is scheduled to receive a wakeup.
Trait Implementations
Auto Trait Implementations
impl<R> RefUnwindSafe for Lines<R> where
R: RefUnwindSafe,
impl<R> UnwindSafe for Lines<R> where
R: UnwindSafe,
Blanket Implementations
Mutably borrows from an owned value. Read more
fn instrument(self, span: Span) -> Instrumented<Self>ⓘNotable traits for Instrumented<T>impl<T> Future for Instrumented<T> where
T: Future, type Output = <T as Future>::Output;
fn instrument(self, span: Span) -> Instrumented<Self>ⓘNotable traits for Instrumented<T>impl<T> Future for Instrumented<T> where
T: Future, type Output = <T as Future>::Output;
impl<T> Future for Instrumented<T> where
T: Future, type Output = <T as Future>::Output;
fn in_current_span(self) -> Instrumented<Self>ⓘNotable traits for Instrumented<T>impl<T> Future for Instrumented<T> where
T: Future, type Output = <T as Future>::Output;
fn in_current_span(self) -> Instrumented<Self>ⓘNotable traits for Instrumented<T>impl<T> Future for Instrumented<T> where
T: Future, type Output = <T as Future>::Output;
impl<T> Future for Instrumented<T> where
T: Future, type Output = <T as Future>::Output;
fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self>ⓘNotable traits for WithDispatch<T>impl<T> Future for WithDispatch<T> where
T: Future, type Output = <T as Future>::Output;
where
S: Into<Dispatch>,
fn with_subscriber<S>(self, subscriber: S) -> WithDispatch<Self>ⓘNotable traits for WithDispatch<T>impl<T> Future for WithDispatch<T> where
T: Future, type Output = <T as Future>::Output;
where
S: Into<Dispatch>,
impl<T> Future for WithDispatch<T> where
T: Future, type Output = <T as Future>::Output;
Attaches the provided Subscriber
to this type, returning a
WithDispatch
wrapper. Read more
fn with_current_subscriber(self) -> WithDispatch<Self>ⓘNotable traits for WithDispatch<T>impl<T> Future for WithDispatch<T> where
T: Future, type Output = <T as Future>::Output;
fn with_current_subscriber(self) -> WithDispatch<Self>ⓘNotable traits for WithDispatch<T>impl<T> Future for WithDispatch<T> where
T: Future, type Output = <T as Future>::Output;
impl<T> Future for WithDispatch<T> where
T: Future, type Output = <T as Future>::Output;
Attaches the current default Subscriber
to this type, returning a
WithDispatch
wrapper. Read more