impl<T> SyncSender<T>

fn send(self: &Self, t: T) -> Result<(), SendError<T>>

Sends a value on this synchronous channel.

This function will block until space in the internal buffer becomes available or a receiver is available to hand off the message to.

Note that a successful send does not guarantee that the receiver will ever see the data if there is a buffer on this channel. Items may be enqueued in the internal buffer for the receiver to receive at a later time. If the buffer size is 0, however, the channel becomes a rendezvous channel and it guarantees that the receiver has indeed received the data if this function returns success.

This function will never panic, but it may return Err if the Receiver has disconnected and is no longer able to receive information.

Examples

use std::sync::mpsc::sync_channel;
use std::thread;

// Create a rendezvous sync_channel with buffer size 0
let (sync_sender, receiver) = sync_channel(0);

thread::spawn(move || {
   println!("sending message...");
   sync_sender.send(1).unwrap();
   // Thread is now blocked until the message is received

   println!("...message received!");
});

let msg = receiver.recv().unwrap();
assert_eq!(1, msg);

fn try_send(self: &Self, t: T) -> Result<(), TrySendError<T>>

Attempts to send a value on this channel without blocking.

This method differs from send by returning immediately if the channel's buffer is full or no receiver is waiting to acquire some data. Compared with send, this function has two failure cases instead of one (one for disconnection, one for a full buffer).

See send for notes about guarantees of whether the receiver has received the data or not if this function is successful.

Examples

use std::sync::mpsc::sync_channel;
use std::thread;

// Create a sync_channel with buffer size 1
let (sync_sender, receiver) = sync_channel(1);
let sync_sender2 = sync_sender.clone();

// First thread owns sync_sender
let handle1 = thread::spawn(move || {
    sync_sender.send(1).unwrap();
    sync_sender.send(2).unwrap();
    // Thread blocked
});

// Second thread owns sync_sender2
let handle2 = thread::spawn(move || {
    // This will return an error and send
    // no message if the buffer is full
    let _ = sync_sender2.try_send(3);
});

let mut msg;
msg = receiver.recv().unwrap();
println!("message {msg} received");

msg = receiver.recv().unwrap();
println!("message {msg} received");

// Third message may have never been sent
match receiver.try_recv() {
    Ok(msg) => println!("message {msg} received"),
    Err(_) => println!("the third message was never sent"),
}

// Wait for threads to complete
handle1.join().unwrap();
handle2.join().unwrap();

impl<T> Any for SyncSender<T>

fn type_id(self: &Self) -> TypeId

impl<T> Borrow for SyncSender<T>

fn borrow(self: &Self) -> &T

impl<T> BorrowMut for SyncSender<T>

fn borrow_mut(self: &mut Self) -> &mut T

impl<T> Clone for SyncSender<T>

fn clone(self: &Self) -> SyncSender<T>

impl<T> CloneToUninit for SyncSender<T>

unsafe fn clone_to_uninit(self: &Self, dest: *mut u8)

impl<T> Debug for SyncSender<T>

fn fmt(self: &Self, f: &mut fmt::Formatter<'_>) -> fmt::Result

impl<T> Freeze for SyncSender<T>

impl<T> From for SyncSender<T>

fn from(t: T) -> T

Returns the argument unchanged.

impl<T> RefUnwindSafe for SyncSender<T>

impl<T> Sync for SyncSender<T>

impl<T> ToOwned for SyncSender<T>

fn to_owned(self: &Self) -> T

fn clone_into(self: &Self, target: &mut T)

impl<T> Unpin for SyncSender<T>

impl<T> UnwindSafe for SyncSender<T>

impl<T, U> Into for SyncSender<T>

fn into(self: Self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of [From]<T> for U chooses to do.

impl<T, U> TryFrom for SyncSender<T>

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

impl<T, U> TryInto for SyncSender<T>

fn try_into(self: Self) -> Result<U, <U as TryFrom<T>>::Error>

impl<T: Send> Send for SyncSender<T>