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use std::error;
use std::fmt;
/// An error returned from the [`send`] method.
///
/// The message could not be sent because the channel is disconnected.
///
/// The error contains the message so it can be recovered.
///
/// [`send`]: super::Sender::send
#[derive(PartialEq, Eq, Clone, Copy)]
pub struct SendError<T>(pub T);
/// An error returned from the [`try_send`] method.
///
/// The error contains the message being sent so it can be recovered.
///
/// [`try_send`]: super::Sender::try_send
#[derive(PartialEq, Eq, Clone, Copy)]
pub enum TrySendError<T> {
/// The message could not be sent because the channel is full.
///
/// If this is a zero-capacity channel, then the error indicates that there was no receiver
/// available to receive the message at the time.
Full(T),
/// The message could not be sent because the channel is disconnected.
Disconnected(T),
}
/// An error returned from the [`send_timeout`] method.
///
/// The error contains the message being sent so it can be recovered.
///
/// [`send_timeout`]: super::Sender::send_timeout
#[derive(PartialEq, Eq, Clone, Copy)]
pub enum SendTimeoutError<T> {
/// The message could not be sent because the channel is full and the operation timed out.
///
/// If this is a zero-capacity channel, then the error indicates that there was no receiver
/// available to receive the message and the operation timed out.
Timeout(T),
/// The message could not be sent because the channel is disconnected.
Disconnected(T),
}
/// An error returned from the [`recv`] method.
///
/// A message could not be received because the channel is empty and disconnected.
///
/// [`recv`]: super::Receiver::recv
#[derive(PartialEq, Eq, Clone, Copy, Debug)]
pub struct RecvError;
/// An error returned from the [`try_recv`] method.
///
/// [`try_recv`]: super::Receiver::try_recv
#[derive(PartialEq, Eq, Clone, Copy, Debug)]
pub enum TryRecvError {
/// A message could not be received because the channel is empty.
///
/// If this is a zero-capacity channel, then the error indicates that there was no sender
/// available to send a message at the time.
Empty,
/// The message could not be received because the channel is empty and disconnected.
Disconnected,
}
/// An error returned from the [`recv_timeout`] method.
///
/// [`recv_timeout`]: super::Receiver::recv_timeout
#[derive(PartialEq, Eq, Clone, Copy, Debug)]
pub enum RecvTimeoutError {
/// A message could not be received because the channel is empty and the operation timed out.
///
/// If this is a zero-capacity channel, then the error indicates that there was no sender
/// available to send a message and the operation timed out.
Timeout,
/// The message could not be received because the channel is empty and disconnected.
Disconnected,
}
/// An error returned from the [`try_select`] method.
///
/// Failed because none of the channel operations were ready.
///
/// [`try_select`]: super::Select::try_select
#[derive(PartialEq, Eq, Clone, Copy, Debug)]
pub struct TrySelectError;
/// An error returned from the [`select_timeout`] method.
///
/// Failed because none of the channel operations became ready before the timeout.
///
/// [`select_timeout`]: super::Select::select_timeout
#[derive(PartialEq, Eq, Clone, Copy, Debug)]
pub struct SelectTimeoutError;
/// An error returned from the [`try_ready`] method.
///
/// Failed because none of the channel operations were ready.
///
/// [`try_ready`]: super::Select::try_ready
#[derive(PartialEq, Eq, Clone, Copy, Debug)]
pub struct TryReadyError;
/// An error returned from the [`ready_timeout`] method.
///
/// Failed because none of the channel operations became ready before the timeout.
///
/// [`ready_timeout`]: super::Select::ready_timeout
#[derive(PartialEq, Eq, Clone, Copy, Debug)]
pub struct ReadyTimeoutError;
impl<T> fmt::Debug for SendError<T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
"SendError(..)".fmt(f)
}
}
impl<T> fmt::Display for SendError<T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
"sending on a disconnected channel".fmt(f)
}
}
impl<T: Send> error::Error for SendError<T> {}
impl<T> SendError<T> {
/// Unwraps the message.
///
/// # Examples
///
/// ```
/// use crossbeam_channel::unbounded;
///
/// let (s, r) = unbounded();
/// drop(r);
///
/// if let Err(err) = s.send("foo") {
/// assert_eq!(err.into_inner(), "foo");
/// }
/// ```
pub fn into_inner(self) -> T {
self.0
}
}
impl<T> fmt::Debug for TrySendError<T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match *self {
TrySendError::Full(..) => "Full(..)".fmt(f),
TrySendError::Disconnected(..) => "Disconnected(..)".fmt(f),
}
}
}
impl<T> fmt::Display for TrySendError<T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match *self {
TrySendError::Full(..) => "sending on a full channel".fmt(f),
TrySendError::Disconnected(..) => "sending on a disconnected channel".fmt(f),
}
}
}
impl<T: Send> error::Error for TrySendError<T> {}
impl<T> From<SendError<T>> for TrySendError<T> {
fn from(err: SendError<T>) -> TrySendError<T> {
match err {
SendError(t) => TrySendError::Disconnected(t),
}
}
}
impl<T> TrySendError<T> {
/// Unwraps the message.
///
/// # Examples
///
/// ```
/// use crossbeam_channel::bounded;
///
/// let (s, r) = bounded(0);
///
/// if let Err(err) = s.try_send("foo") {
/// assert_eq!(err.into_inner(), "foo");
/// }
/// ```
pub fn into_inner(self) -> T {
match self {
TrySendError::Full(v) => v,
TrySendError::Disconnected(v) => v,
}
}
/// Returns `true` if the send operation failed because the channel is full.
pub fn is_full(&self) -> bool {
match self {
TrySendError::Full(_) => true,
_ => false,
}
}
/// Returns `true` if the send operation failed because the channel is disconnected.
pub fn is_disconnected(&self) -> bool {
match self {
TrySendError::Disconnected(_) => true,
_ => false,
}
}
}
impl<T> fmt::Debug for SendTimeoutError<T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
"SendTimeoutError(..)".fmt(f)
}
}
impl<T> fmt::Display for SendTimeoutError<T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match *self {
SendTimeoutError::Timeout(..) => "timed out waiting on send operation".fmt(f),
SendTimeoutError::Disconnected(..) => "sending on a disconnected channel".fmt(f),
}
}
}
impl<T: Send> error::Error for SendTimeoutError<T> {}
impl<T> From<SendError<T>> for SendTimeoutError<T> {
fn from(err: SendError<T>) -> SendTimeoutError<T> {
match err {
SendError(e) => SendTimeoutError::Disconnected(e),
}
}
}
impl<T> SendTimeoutError<T> {
/// Unwraps the message.
///
/// # Examples
///
/// ```
/// use std::time::Duration;
/// use crossbeam_channel::unbounded;
///
/// let (s, r) = unbounded();
///
/// if let Err(err) = s.send_timeout("foo", Duration::from_secs(1)) {
/// assert_eq!(err.into_inner(), "foo");
/// }
/// ```
pub fn into_inner(self) -> T {
match self {
SendTimeoutError::Timeout(v) => v,
SendTimeoutError::Disconnected(v) => v,
}
}
/// Returns `true` if the send operation timed out.
pub fn is_timeout(&self) -> bool {
match self {
SendTimeoutError::Timeout(_) => true,
_ => false,
}
}
/// Returns `true` if the send operation failed because the channel is disconnected.
pub fn is_disconnected(&self) -> bool {
match self {
SendTimeoutError::Disconnected(_) => true,
_ => false,
}
}
}
impl fmt::Display for RecvError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
"receiving on an empty and disconnected channel".fmt(f)
}
}
impl error::Error for RecvError {}
impl fmt::Display for TryRecvError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match *self {
TryRecvError::Empty => "receiving on an empty channel".fmt(f),
TryRecvError::Disconnected => "receiving on an empty and disconnected channel".fmt(f),
}
}
}
impl error::Error for TryRecvError {}
impl From<RecvError> for TryRecvError {
fn from(err: RecvError) -> TryRecvError {
match err {
RecvError => TryRecvError::Disconnected,
}
}
}
impl TryRecvError {
/// Returns `true` if the receive operation failed because the channel is empty.
pub fn is_empty(&self) -> bool {
match self {
TryRecvError::Empty => true,
_ => false,
}
}
/// Returns `true` if the receive operation failed because the channel is disconnected.
pub fn is_disconnected(&self) -> bool {
match self {
TryRecvError::Disconnected => true,
_ => false,
}
}
}
impl fmt::Display for RecvTimeoutError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match *self {
RecvTimeoutError::Timeout => "timed out waiting on receive operation".fmt(f),
RecvTimeoutError::Disconnected => "channel is empty and disconnected".fmt(f),
}
}
}
impl error::Error for RecvTimeoutError {}
impl From<RecvError> for RecvTimeoutError {
fn from(err: RecvError) -> RecvTimeoutError {
match err {
RecvError => RecvTimeoutError::Disconnected,
}
}
}
impl RecvTimeoutError {
/// Returns `true` if the receive operation timed out.
pub fn is_timeout(&self) -> bool {
match self {
RecvTimeoutError::Timeout => true,
_ => false,
}
}
/// Returns `true` if the receive operation failed because the channel is disconnected.
pub fn is_disconnected(&self) -> bool {
match self {
RecvTimeoutError::Disconnected => true,
_ => false,
}
}
}
impl fmt::Display for TrySelectError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
"all operations in select would block".fmt(f)
}
}
impl error::Error for TrySelectError {}
impl fmt::Display for SelectTimeoutError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
"timed out waiting on select".fmt(f)
}
}
impl error::Error for SelectTimeoutError {}