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id="755">755</span> <span id="756">756</span> <span id="757">757</span> <span id="758">758</span> <span id="759">759</span> <span id="760">760</span> <span id="761">761</span> <span id="762">762</span> <span id="763">763</span> <span id="764">764</span> <span id="765">765</span> <span id="766">766</span> <span id="767">767</span> <span id="768">768</span> <span id="769">769</span> <span id="770">770</span> <span id="771">771</span> <span id="772">772</span> <span id="773">773</span> <span id="774">774</span> <span id="775">775</span> <span id="776">776</span> <span id="777">777</span> <span id="778">778</span> <span id="779">779</span> <span id="780">780</span> <span id="781">781</span> <span id="782">782</span> <span id="783">783</span> <span id="784">784</span> <span id="785">785</span> <span id="786">786</span> <span id="787">787</span> <span id="788">788</span> <span id="789">789</span> <span id="790">790</span> <span id="791">791</span> </pre><pre class="rust "> <span class="comment">// Copyright 2013-2014 The Rust Project Developers. See the COPYRIGHT</span> <span class="comment">// file at the top-level directory of this distribution and at</span> <span class="comment">// http://rust-lang.org/COPYRIGHT.</span> <span class="comment">//</span> <span class="comment">// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or</span> <span class="comment">// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license</span> <span class="comment">// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your</span> <span class="comment">// option. This file may not be copied, modified, or distributed</span> <span class="comment">// except according to those terms.</span> <span class="doccomment">//! Selection over an array of receivers</span> <span class="doccomment">//!</span> <span class="doccomment">//! This module contains the implementation machinery necessary for selecting</span> <span class="doccomment">//! over a number of receivers. One large goal of this module is to provide an</span> <span class="doccomment">//! efficient interface to selecting over any receiver of any type.</span> <span class="doccomment">//!</span> <span class="doccomment">//! This is achieved through an architecture of a "receiver set" in which</span> <span class="doccomment">//! receivers are added to a set and then the entire set is waited on at once.</span> <span class="doccomment">//! The set can be waited on multiple times to prevent re-adding each receiver</span> <span class="doccomment">//! to the set.</span> <span class="doccomment">//!</span> <span class="doccomment">//! Usage of this module is currently encouraged to go through the use of the</span> <span class="doccomment">//! `select!` macro. This macro allows naturally binding of variables to the</span> <span class="doccomment">//! received values of receivers in a much more natural syntax then usage of the</span> <span class="doccomment">//! `Select` structure directly.</span> <span class="doccomment">//!</span> <span class="doccomment">//! # Examples</span> <span class="doccomment">//!</span> <span class="doccomment">//! ```rust</span> <span class="doccomment">//! #![feature(mpsc_select)]</span> <span class="doccomment">//!</span> <span class="doccomment">//! use std::sync::mpsc::channel;</span> <span class="doccomment">//!</span> <span class="doccomment">//! let (tx1, rx1) = channel();</span> <span class="doccomment">//! let (tx2, rx2) = channel();</span> <span class="doccomment">//!</span> <span class="doccomment">//! tx1.send(1).unwrap();</span> <span class="doccomment">//! tx2.send(2).unwrap();</span> <span class="doccomment">//!</span> <span class="doccomment">//! select! {</span> <span class="doccomment">//! val = rx1.recv() => {</span> <span class="doccomment">//! assert_eq!(val.unwrap(), 1);</span> <span class="doccomment">//! },</span> <span class="doccomment">//! val = rx2.recv() => {</span> <span class="doccomment">//! assert_eq!(val.unwrap(), 2);</span> <span class="doccomment">//! }</span> <span class="doccomment">//! }</span> <span class="doccomment">//! ```</span> <span class="attribute">#<span class="op">!</span>[<span class="ident">allow</span>(<span class="ident">dead_code</span>)]</span> <span class="attribute">#<span class="op">!</span>[<span class="ident">unstable</span>(<span class="ident">feature</span> <span class="op">=</span> <span class="string">"mpsc_select"</span>, <span class="ident">reason</span> <span class="op">=</span> <span class="string">"This implementation, while likely sufficient, is unsafe and \ likely to be error prone. At some point in the future this \ module will likely be replaced, and it is currently \ unknown how much API breakage that will cause. The ability \ to select over a number of channels will remain forever, \ but no guarantees beyond this are being made"</span>, <span class="ident">issue</span> <span class="op">=</span> <span class="string">"27800"</span>)]</span> <span class="kw">use</span> <span class="ident">fmt</span>; <span class="kw">use</span> <span class="ident">core</span>::<span class="ident">cell</span>::{<span class="ident">Cell</span>, <span class="ident">UnsafeCell</span>}; <span class="kw">use</span> <span class="ident">core</span>::<span class="ident">marker</span>; <span class="kw">use</span> <span class="ident">core</span>::<span class="ident">ptr</span>; <span class="kw">use</span> <span class="ident">core</span>::<span class="ident">usize</span>; <span class="kw">use</span> <span class="ident">sync</span>::<span class="ident">mpsc</span>::{<span class="ident">Receiver</span>, <span class="ident">RecvError</span>}; <span class="kw">use</span> <span class="ident">sync</span>::<span class="ident">mpsc</span>::<span class="ident">blocking</span>::{<span class="self">self</span>, <span class="ident">SignalToken</span>}; <span class="doccomment">/// The "receiver set" of the select interface. This structure is used to manage</span> <span class="doccomment">/// a set of receivers which are being selected over.</span> <span class="kw">pub</span> <span class="kw">struct</span> <span class="ident">Select</span> { <span class="ident">inner</span>: <span class="ident">UnsafeCell</span><span class="op"><</span><span class="ident">SelectInner</span><span class="op">></span>, <span class="ident">next_id</span>: <span class="ident">Cell</span><span class="op"><</span><span class="ident">usize</span><span class="op">></span>, } <span class="kw">struct</span> <span class="ident">SelectInner</span> { <span class="ident">head</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">Handle</span><span class="op"><</span><span class="lifetime">'static</span>, ()<span class="op">></span>, <span class="ident">tail</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">Handle</span><span class="op"><</span><span class="lifetime">'static</span>, ()<span class="op">></span>, } <span class="kw">impl</span> <span class="op">!</span><span class="ident">marker</span>::<span class="ident">Send</span> <span class="kw">for</span> <span class="ident">Select</span> {} <span class="doccomment">/// A handle to a receiver which is currently a member of a `Select` set of</span> <span class="doccomment">/// receivers. This handle is used to keep the receiver in the set as well as</span> <span class="doccomment">/// interact with the underlying receiver.</span> <span class="kw">pub</span> <span class="kw">struct</span> <span class="ident">Handle</span><span class="op"><</span><span class="lifetime">'rx</span>, <span class="ident">T</span>:<span class="ident">Send</span><span class="op">+</span><span class="lifetime">'rx</span><span class="op">></span> { <span class="doccomment">/// The ID of this handle, used to compare against the return value of</span> <span class="doccomment">/// `Select::wait()`</span> <span class="ident">id</span>: <span class="ident">usize</span>, <span class="ident">selector</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">SelectInner</span>, <span class="ident">next</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">Handle</span><span class="op"><</span><span class="lifetime">'static</span>, ()<span class="op">></span>, <span class="ident">prev</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">Handle</span><span class="op"><</span><span class="lifetime">'static</span>, ()<span class="op">></span>, <span class="ident">added</span>: <span class="ident">bool</span>, <span class="ident">packet</span>: <span class="kw-2">&</span><span class="lifetime">'rx</span> (<span class="ident">Packet</span><span class="op">+</span><span class="lifetime">'rx</span>), <span class="comment">// due to our fun transmutes, we be sure to place this at the end. (nothing</span> <span class="comment">// previous relies on T)</span> <span class="ident">rx</span>: <span class="kw-2">&</span><span class="lifetime">'rx</span> <span class="ident">Receiver</span><span class="op"><</span><span class="ident">T</span><span class="op">></span>, } <span class="kw">struct</span> <span class="ident">Packets</span> { <span class="ident">cur</span>: <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">Handle</span><span class="op"><</span><span class="lifetime">'static</span>, ()<span class="op">></span> } <span class="attribute">#[<span class="ident">doc</span>(<span class="ident">hidden</span>)]</span> <span class="attribute">#[<span class="ident">derive</span>(<span class="ident">PartialEq</span>, <span class="ident">Eq</span>)]</span> <span class="kw">pub</span> <span class="kw">enum</span> <span class="ident">StartResult</span> { <span class="ident">Installed</span>, <span class="ident">Abort</span>, } <span class="attribute">#[<span class="ident">doc</span>(<span class="ident">hidden</span>)]</span> <span class="kw">pub</span> <span class="kw">trait</span> <span class="ident">Packet</span> { <span class="kw">fn</span> <span class="ident">can_recv</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-></span> <span class="ident">bool</span>; <span class="kw">fn</span> <span class="ident">start_selection</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">token</span>: <span class="ident">SignalToken</span>) <span class="op">-></span> <span class="ident">StartResult</span>; <span class="kw">fn</span> <span class="ident">abort_selection</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-></span> <span class="ident">bool</span>; } <span class="kw">impl</span> <span class="ident">Select</span> { <span class="doccomment">/// Creates a new selection structure. This set is initially empty.</span> <span class="doccomment">///</span> <span class="doccomment">/// Usage of this struct directly can sometimes be burdensome, and usage is much easier through</span> <span class="doccomment">/// the `select!` macro.</span> <span class="doccomment">///</span> <span class="doccomment">/// # Examples</span> <span class="doccomment">///</span> <span class="doccomment">/// ```</span> <span class="doccomment">/// #![feature(mpsc_select)]</span> <span class="doccomment">///</span> <span class="doccomment">/// use std::sync::mpsc::Select;</span> <span class="doccomment">///</span> <span class="doccomment">/// let select = Select::new();</span> <span class="doccomment">/// ```</span> <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">new</span>() <span class="op">-></span> <span class="ident">Select</span> { <span class="ident">Select</span> { <span class="ident">inner</span>: <span class="ident">UnsafeCell</span>::<span class="ident">new</span>(<span class="ident">SelectInner</span> { <span class="ident">head</span>: <span class="ident">ptr</span>::<span class="ident">null_mut</span>(), <span class="ident">tail</span>: <span class="ident">ptr</span>::<span class="ident">null_mut</span>(), }), <span class="ident">next_id</span>: <span class="ident">Cell</span>::<span class="ident">new</span>(<span class="number">1</span>), } } <span class="doccomment">/// Creates a new handle into this receiver set for a new receiver. Note</span> <span class="doccomment">/// that this does *not* add the receiver to the receiver set, for that you</span> <span class="doccomment">/// must call the `add` method on the handle itself.</span> <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">handle</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">T</span>: <span class="ident">Send</span><span class="op">></span>(<span class="kw-2">&</span><span class="lifetime">'a</span> <span class="self">self</span>, <span class="ident">rx</span>: <span class="kw-2">&</span><span class="lifetime">'a</span> <span class="ident">Receiver</span><span class="op"><</span><span class="ident">T</span><span class="op">></span>) <span class="op">-></span> <span class="ident">Handle</span><span class="op"><</span><span class="lifetime">'a</span>, <span class="ident">T</span><span class="op">></span> { <span class="kw">let</span> <span class="ident">id</span> <span class="op">=</span> <span class="self">self</span>.<span class="ident">next_id</span>.<span class="ident">get</span>(); <span class="self">self</span>.<span class="ident">next_id</span>.<span class="ident">set</span>(<span class="ident">id</span> <span class="op">+</span> <span class="number">1</span>); <span class="ident">Handle</span> { <span class="ident">id</span>: <span class="ident">id</span>, <span class="ident">selector</span>: <span class="self">self</span>.<span class="ident">inner</span>.<span class="ident">get</span>(), <span class="ident">next</span>: <span class="ident">ptr</span>::<span class="ident">null_mut</span>(), <span class="ident">prev</span>: <span class="ident">ptr</span>::<span class="ident">null_mut</span>(), <span class="ident">added</span>: <span class="bool-val">false</span>, <span class="ident">rx</span>: <span class="ident">rx</span>, <span class="ident">packet</span>: <span class="ident">rx</span>, } } <span class="doccomment">/// Waits for an event on this receiver set. The returned value is *not* an</span> <span class="doccomment">/// index, but rather an id. This id can be queried against any active</span> <span class="doccomment">/// `Handle` structures (each one has an `id` method). The handle with</span> <span class="doccomment">/// the matching `id` will have some sort of event available on it. The</span> <span class="doccomment">/// event could either be that data is available or the corresponding</span> <span class="doccomment">/// channel has been closed.</span> <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">wait</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-></span> <span class="ident">usize</span> { <span class="self">self</span>.<span class="ident">wait2</span>(<span class="bool-val">true</span>) } <span class="doccomment">/// Helper method for skipping the preflight checks during testing</span> <span class="kw">fn</span> <span class="ident">wait2</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">do_preflight_checks</span>: <span class="ident">bool</span>) <span class="op">-></span> <span class="ident">usize</span> { <span class="comment">// Note that this is currently an inefficient implementation. We in</span> <span class="comment">// theory have knowledge about all receivers in the set ahead of time,</span> <span class="comment">// so this method shouldn't really have to iterate over all of them yet</span> <span class="comment">// again. The idea with this "receiver set" interface is to get the</span> <span class="comment">// interface right this time around, and later this implementation can</span> <span class="comment">// be optimized.</span> <span class="comment">//</span> <span class="comment">// This implementation can be summarized by:</span> <span class="comment">//</span> <span class="comment">// fn select(receivers) {</span> <span class="comment">// if any receiver ready { return ready index }</span> <span class="comment">// deschedule {</span> <span class="comment">// block on all receivers</span> <span class="comment">// }</span> <span class="comment">// unblock on all receivers</span> <span class="comment">// return ready index</span> <span class="comment">// }</span> <span class="comment">//</span> <span class="comment">// Most notably, the iterations over all of the receivers shouldn't be</span> <span class="comment">// necessary.</span> <span class="kw">unsafe</span> { <span class="comment">// Stage 1: preflight checks. Look for any packets ready to receive</span> <span class="kw">if</span> <span class="ident">do_preflight_checks</span> { <span class="kw">for</span> <span class="ident">handle</span> <span class="kw">in</span> <span class="self">self</span>.<span class="ident">iter</span>() { <span class="kw">if</span> (<span class="kw-2">*</span><span class="ident">handle</span>).<span class="ident">packet</span>.<span class="ident">can_recv</span>() { <span class="kw">return</span> (<span class="kw-2">*</span><span class="ident">handle</span>).<span class="ident">id</span>(); } } } <span class="comment">// Stage 2: begin the blocking process</span> <span class="comment">//</span> <span class="comment">// Create a number of signal tokens, and install each one</span> <span class="comment">// sequentially until one fails. If one fails, then abort the</span> <span class="comment">// selection on the already-installed tokens.</span> <span class="kw">let</span> (<span class="ident">wait_token</span>, <span class="ident">signal_token</span>) <span class="op">=</span> <span class="ident">blocking</span>::<span class="ident">tokens</span>(); <span class="kw">for</span> (<span class="ident">i</span>, <span class="ident">handle</span>) <span class="kw">in</span> <span class="self">self</span>.<span class="ident">iter</span>().<span class="ident">enumerate</span>() { <span class="kw">match</span> (<span class="kw-2">*</span><span class="ident">handle</span>).<span class="ident">packet</span>.<span class="ident">start_selection</span>(<span class="ident">signal_token</span>.<span class="ident">clone</span>()) { <span class="ident">StartResult</span>::<span class="ident">Installed</span> <span class="op">=></span> {} <span class="ident">StartResult</span>::<span class="ident">Abort</span> <span class="op">=></span> { <span class="comment">// Go back and abort the already-begun selections</span> <span class="kw">for</span> <span class="ident">handle</span> <span class="kw">in</span> <span class="self">self</span>.<span class="ident">iter</span>().<span class="ident">take</span>(<span class="ident">i</span>) { (<span class="kw-2">*</span><span class="ident">handle</span>).<span class="ident">packet</span>.<span class="ident">abort_selection</span>(); } <span class="kw">return</span> (<span class="kw-2">*</span><span class="ident">handle</span>).<span class="ident">id</span>; } } } <span class="comment">// Stage 3: no messages available, actually block</span> <span class="ident">wait_token</span>.<span class="ident">wait</span>(); <span class="comment">// Stage 4: there *must* be message available; find it.</span> <span class="comment">//</span> <span class="comment">// Abort the selection process on each receiver. If the abort</span> <span class="comment">// process returns `true`, then that means that the receiver is</span> <span class="comment">// ready to receive some data. Note that this also means that the</span> <span class="comment">// receiver may have yet to have fully read the `to_wake` field and</span> <span class="comment">// woken us up (although the wakeup is guaranteed to fail).</span> <span class="comment">//</span> <span class="comment">// This situation happens in the window of where a sender invokes</span> <span class="comment">// increment(), sees -1, and then decides to wake up the thread. After</span> <span class="comment">// all this is done, the sending thread will set `selecting` to</span> <span class="comment">// `false`. Until this is done, we cannot return. If we were to</span> <span class="comment">// return, then a sender could wake up a receiver which has gone</span> <span class="comment">// back to sleep after this call to `select`.</span> <span class="comment">//</span> <span class="comment">// Note that it is a "fairly small window" in which an increment()</span> <span class="comment">// views that it should wake a thread up until the `selecting` bit</span> <span class="comment">// is set to false. For now, the implementation currently just spins</span> <span class="comment">// in a yield loop. This is very distasteful, but this</span> <span class="comment">// implementation is already nowhere near what it should ideally be.</span> <span class="comment">// A rewrite should focus on avoiding a yield loop, and for now this</span> <span class="comment">// implementation is tying us over to a more efficient "don't</span> <span class="comment">// iterate over everything every time" implementation.</span> <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">ready_id</span> <span class="op">=</span> <span class="ident">usize</span>::<span class="ident">MAX</span>; <span class="kw">for</span> <span class="ident">handle</span> <span class="kw">in</span> <span class="self">self</span>.<span class="ident">iter</span>() { <span class="kw">if</span> (<span class="kw-2">*</span><span class="ident">handle</span>).<span class="ident">packet</span>.<span class="ident">abort_selection</span>() { <span class="ident">ready_id</span> <span class="op">=</span> (<span class="kw-2">*</span><span class="ident">handle</span>).<span class="ident">id</span>; } } <span class="comment">// We must have found a ready receiver</span> <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">ready_id</span> <span class="op">!=</span> <span class="ident">usize</span>::<span class="ident">MAX</span>); <span class="kw">return</span> <span class="ident">ready_id</span>; } } <span class="kw">fn</span> <span class="ident">iter</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-></span> <span class="ident">Packets</span> { <span class="ident">Packets</span> { <span class="ident">cur</span>: <span class="kw">unsafe</span> { <span class="kw-2">&</span><span class="kw-2">*</span><span class="self">self</span>.<span class="ident">inner</span>.<span class="ident">get</span>() }.<span class="ident">head</span> } } } <span class="kw">impl</span><span class="op"><</span><span class="lifetime">'rx</span>, <span class="ident">T</span>: <span class="ident">Send</span><span class="op">></span> <span class="ident">Handle</span><span class="op"><</span><span class="lifetime">'rx</span>, <span class="ident">T</span><span class="op">></span> { <span class="doccomment">/// Retrieves the id of this handle.</span> <span class="attribute">#[<span class="ident">inline</span>]</span> <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">id</span>(<span class="kw-2">&</span><span class="self">self</span>) <span class="op">-></span> <span class="ident">usize</span> { <span class="self">self</span>.<span class="ident">id</span> } <span class="doccomment">/// Blocks to receive a value on the underlying receiver, returning `Some` on</span> <span class="doccomment">/// success or `None` if the channel disconnects. This function has the same</span> <span class="doccomment">/// semantics as `Receiver.recv`</span> <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">recv</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>) <span class="op">-></span> <span class="prelude-ty">Result</span><span class="op"><</span><span class="ident">T</span>, <span class="ident">RecvError</span><span class="op">></span> { <span class="self">self</span>.<span class="ident">rx</span>.<span class="ident">recv</span>() } <span class="doccomment">/// Adds this handle to the receiver set that the handle was created from. This</span> <span class="doccomment">/// method can be called multiple times, but it has no effect if `add` was</span> <span class="doccomment">/// called previously.</span> <span class="doccomment">///</span> <span class="doccomment">/// This method is unsafe because it requires that the `Handle` is not moved</span> <span class="doccomment">/// while it is added to the `Select` set.</span> <span class="kw">pub</span> <span class="kw">unsafe</span> <span class="kw">fn</span> <span class="ident">add</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>) { <span class="kw">if</span> <span class="self">self</span>.<span class="ident">added</span> { <span class="kw">return</span> } <span class="kw">let</span> <span class="ident">selector</span> <span class="op">=</span> <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="kw-2">*</span><span class="self">self</span>.<span class="ident">selector</span>; <span class="kw">let</span> <span class="ident">me</span> <span class="op">=</span> <span class="self">self</span> <span class="kw">as</span> <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">Handle</span><span class="op"><</span><span class="lifetime">'rx</span>, <span class="ident">T</span><span class="op">></span> <span class="kw">as</span> <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">Handle</span><span class="op"><</span><span class="lifetime">'static</span>, ()<span class="op">></span>; <span class="kw">if</span> <span class="ident">selector</span>.<span class="ident">head</span>.<span class="ident">is_null</span>() { <span class="ident">selector</span>.<span class="ident">head</span> <span class="op">=</span> <span class="ident">me</span>; <span class="ident">selector</span>.<span class="ident">tail</span> <span class="op">=</span> <span class="ident">me</span>; } <span class="kw">else</span> { (<span class="kw-2">*</span><span class="ident">me</span>).<span class="ident">prev</span> <span class="op">=</span> <span class="ident">selector</span>.<span class="ident">tail</span>; <span class="macro">assert</span><span class="macro">!</span>((<span class="kw-2">*</span><span class="ident">me</span>).<span class="ident">next</span>.<span class="ident">is_null</span>()); (<span class="kw-2">*</span><span class="ident">selector</span>.<span class="ident">tail</span>).<span class="ident">next</span> <span class="op">=</span> <span class="ident">me</span>; <span class="ident">selector</span>.<span class="ident">tail</span> <span class="op">=</span> <span class="ident">me</span>; } <span class="self">self</span>.<span class="ident">added</span> <span class="op">=</span> <span class="bool-val">true</span>; } <span class="doccomment">/// Removes this handle from the `Select` set. This method is unsafe because</span> <span class="doccomment">/// it has no guarantee that the `Handle` was not moved since `add` was</span> <span class="doccomment">/// called.</span> <span class="kw">pub</span> <span class="kw">unsafe</span> <span class="kw">fn</span> <span class="ident">remove</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>) { <span class="kw">if</span> <span class="op">!</span><span class="self">self</span>.<span class="ident">added</span> { <span class="kw">return</span> } <span class="kw">let</span> <span class="ident">selector</span> <span class="op">=</span> <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="kw-2">*</span><span class="self">self</span>.<span class="ident">selector</span>; <span class="kw">let</span> <span class="ident">me</span> <span class="op">=</span> <span class="self">self</span> <span class="kw">as</span> <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">Handle</span><span class="op"><</span><span class="lifetime">'rx</span>, <span class="ident">T</span><span class="op">></span> <span class="kw">as</span> <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">Handle</span><span class="op"><</span><span class="lifetime">'static</span>, ()<span class="op">></span>; <span class="kw">if</span> <span class="self">self</span>.<span class="ident">prev</span>.<span class="ident">is_null</span>() { <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">selector</span>.<span class="ident">head</span>, <span class="ident">me</span>); <span class="ident">selector</span>.<span class="ident">head</span> <span class="op">=</span> <span class="self">self</span>.<span class="ident">next</span>; } <span class="kw">else</span> { (<span class="kw-2">*</span><span class="self">self</span>.<span class="ident">prev</span>).<span class="ident">next</span> <span class="op">=</span> <span class="self">self</span>.<span class="ident">next</span>; } <span class="kw">if</span> <span class="self">self</span>.<span class="ident">next</span>.<span class="ident">is_null</span>() { <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">selector</span>.<span class="ident">tail</span>, <span class="ident">me</span>); <span class="ident">selector</span>.<span class="ident">tail</span> <span class="op">=</span> <span class="self">self</span>.<span class="ident">prev</span>; } <span class="kw">else</span> { (<span class="kw-2">*</span><span class="self">self</span>.<span class="ident">next</span>).<span class="ident">prev</span> <span class="op">=</span> <span class="self">self</span>.<span class="ident">prev</span>; } <span class="self">self</span>.<span class="ident">next</span> <span class="op">=</span> <span class="ident">ptr</span>::<span class="ident">null_mut</span>(); <span class="self">self</span>.<span class="ident">prev</span> <span class="op">=</span> <span class="ident">ptr</span>::<span class="ident">null_mut</span>(); <span class="self">self</span>.<span class="ident">added</span> <span class="op">=</span> <span class="bool-val">false</span>; } } <span class="kw">impl</span> <span class="ident">Drop</span> <span class="kw">for</span> <span class="ident">Select</span> { <span class="kw">fn</span> <span class="ident">drop</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>) { <span class="kw">unsafe</span> { <span class="macro">assert</span><span class="macro">!</span>((<span class="kw-2">&</span><span class="kw-2">*</span><span class="self">self</span>.<span class="ident">inner</span>.<span class="ident">get</span>()).<span class="ident">head</span>.<span class="ident">is_null</span>()); <span class="macro">assert</span><span class="macro">!</span>((<span class="kw-2">&</span><span class="kw-2">*</span><span class="self">self</span>.<span class="ident">inner</span>.<span class="ident">get</span>()).<span class="ident">tail</span>.<span class="ident">is_null</span>()); } } } <span class="kw">impl</span><span class="op"><</span><span class="lifetime">'rx</span>, <span class="ident">T</span>: <span class="ident">Send</span><span class="op">></span> <span class="ident">Drop</span> <span class="kw">for</span> <span class="ident">Handle</span><span class="op"><</span><span class="lifetime">'rx</span>, <span class="ident">T</span><span class="op">></span> { <span class="kw">fn</span> <span class="ident">drop</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>) { <span class="kw">unsafe</span> { <span class="self">self</span>.<span class="ident">remove</span>() } } } <span class="kw">impl</span> <span class="ident">Iterator</span> <span class="kw">for</span> <span class="ident">Packets</span> { <span class="kw">type</span> <span class="ident">Item</span> <span class="op">=</span> <span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">Handle</span><span class="op"><</span><span class="lifetime">'static</span>, ()<span class="op">></span>; <span class="kw">fn</span> <span class="ident">next</span>(<span class="kw-2">&</span><span class="kw-2">mut</span> <span class="self">self</span>) <span class="op">-></span> <span class="prelude-ty">Option</span><span class="op"><</span><span class="kw-2">*</span><span class="kw-2">mut</span> <span class="ident">Handle</span><span class="op"><</span><span class="lifetime">'static</span>, ()<span class="op">>></span> { <span class="kw">if</span> <span class="self">self</span>.<span class="ident">cur</span>.<span class="ident">is_null</span>() { <span class="prelude-val">None</span> } <span class="kw">else</span> { <span class="kw">let</span> <span class="ident">ret</span> <span class="op">=</span> <span class="prelude-val">Some</span>(<span class="self">self</span>.<span class="ident">cur</span>); <span class="kw">unsafe</span> { <span class="self">self</span>.<span class="ident">cur</span> <span class="op">=</span> (<span class="kw-2">*</span><span class="self">self</span>.<span class="ident">cur</span>).<span class="ident">next</span>; } <span class="ident">ret</span> } } } <span class="kw">impl</span> <span class="ident">fmt</span>::<span class="ident">Debug</span> <span class="kw">for</span> <span class="ident">Select</span> { <span class="kw">fn</span> <span class="ident">fmt</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">f</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">fmt</span>::<span class="ident">Formatter</span>) <span class="op">-></span> <span class="ident">fmt</span>::<span class="prelude-ty">Result</span> { <span class="macro">write</span><span class="macro">!</span>(<span class="ident">f</span>, <span class="string">"Select {{ .. }}"</span>) } } <span class="kw">impl</span><span class="op"><</span><span class="lifetime">'rx</span>, <span class="ident">T</span>:<span class="ident">Send</span><span class="op">+</span><span class="lifetime">'rx</span><span class="op">></span> <span class="ident">fmt</span>::<span class="ident">Debug</span> <span class="kw">for</span> <span class="ident">Handle</span><span class="op"><</span><span class="lifetime">'rx</span>, <span class="ident">T</span><span class="op">></span> { <span class="kw">fn</span> <span class="ident">fmt</span>(<span class="kw-2">&</span><span class="self">self</span>, <span class="ident">f</span>: <span class="kw-2">&</span><span class="kw-2">mut</span> <span class="ident">fmt</span>::<span class="ident">Formatter</span>) <span class="op">-></span> <span class="ident">fmt</span>::<span class="prelude-ty">Result</span> { <span class="macro">write</span><span class="macro">!</span>(<span class="ident">f</span>, <span class="string">"Handle {{ .. }}"</span>) } } <span class="attribute">#[<span class="ident">allow</span>(<span class="ident">unused_imports</span>)]</span> <span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">all</span>(<span class="ident">test</span>, <span class="ident">not</span>(<span class="ident">target_os</span> <span class="op">=</span> <span class="string">"emscripten"</span>)))]</span> <span class="kw">mod</span> <span class="ident">tests</span> { <span class="kw">use</span> <span class="ident">thread</span>; <span class="kw">use</span> <span class="ident">sync</span>::<span class="ident">mpsc</span>::<span class="kw-2">*</span>; <span class="comment">// Don't use the libstd version so we can pull in the right Select structure</span> <span class="comment">// (std::comm points at the wrong one)</span> <span class="macro">macro_rules</span><span class="macro">!</span> <span class="ident">select</span> { ( $(<span class="macro-nonterminal">$</span><span class="macro-nonterminal">name</span>:<span class="ident">pat</span> <span class="op">=</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">rx</span>:<span class="ident">ident</span>.<span class="macro-nonterminal">$</span><span class="macro-nonterminal">meth</span>:<span class="ident">ident</span>() <span class="op">=></span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">code</span>:<span class="ident">expr</span>),<span class="op">+</span> ) <span class="op">=></span> ({ <span class="kw">let</span> <span class="ident">sel</span> <span class="op">=</span> <span class="ident">Select</span>::<span class="ident">new</span>(); $( <span class="kw">let</span> <span class="kw-2">mut</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">rx</span> <span class="op">=</span> <span class="ident">sel</span>.<span class="ident">handle</span>(<span class="kw-2">&</span><span class="macro-nonterminal">$</span><span class="macro-nonterminal">rx</span>); )<span class="op">+</span> <span class="kw">unsafe</span> { $( <span class="macro-nonterminal">$</span><span class="macro-nonterminal">rx</span>.<span class="ident">add</span>(); )<span class="op">+</span> } <span class="kw">let</span> <span class="ident">ret</span> <span class="op">=</span> <span class="ident">sel</span>.<span class="ident">wait</span>(); $( <span class="kw">if</span> <span class="ident">ret</span> <span class="op">==</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">rx</span>.<span class="ident">id</span>() { <span class="kw">let</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">name</span> <span class="op">=</span> <span class="macro-nonterminal">$</span><span class="macro-nonterminal">rx</span>.<span class="macro-nonterminal">$</span><span class="macro-nonterminal">meth</span>(); <span class="macro-nonterminal">$</span><span class="macro-nonterminal">code</span> } <span class="kw">else</span> )<span class="op">+</span> { <span class="macro">unreachable</span><span class="macro">!</span>() } }) } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">smoke</span>() { <span class="kw">let</span> (<span class="ident">tx1</span>, <span class="ident">rx1</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> (<span class="ident">tx2</span>, <span class="ident">rx2</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="ident">tx1</span>.<span class="ident">send</span>(<span class="number">1</span>).<span class="ident">unwrap</span>(); <span class="macro">select</span><span class="macro">!</span> { <span class="ident">foo</span> <span class="op">=</span> <span class="ident">rx1</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">foo</span>.<span class="ident">unwrap</span>(), <span class="number">1</span>); }, <span class="ident">_bar</span> <span class="op">=</span> <span class="ident">rx2</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">panic</span><span class="macro">!</span>() } } <span class="ident">tx2</span>.<span class="ident">send</span>(<span class="number">2</span>).<span class="ident">unwrap</span>(); <span class="macro">select</span><span class="macro">!</span> { <span class="ident">_foo</span> <span class="op">=</span> <span class="ident">rx1</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">panic</span><span class="macro">!</span>() }, <span class="ident">bar</span> <span class="op">=</span> <span class="ident">rx2</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">bar</span>.<span class="ident">unwrap</span>(), <span class="number">2</span>) } } <span class="ident">drop</span>(<span class="ident">tx1</span>); <span class="macro">select</span><span class="macro">!</span> { <span class="ident">foo</span> <span class="op">=</span> <span class="ident">rx1</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">foo</span>.<span class="ident">is_err</span>()); }, <span class="ident">_bar</span> <span class="op">=</span> <span class="ident">rx2</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">panic</span><span class="macro">!</span>() } } <span class="ident">drop</span>(<span class="ident">tx2</span>); <span class="macro">select</span><span class="macro">!</span> { <span class="ident">bar</span> <span class="op">=</span> <span class="ident">rx2</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">bar</span>.<span class="ident">is_err</span>()); } } } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">smoke2</span>() { <span class="kw">let</span> (<span class="ident">_tx1</span>, <span class="ident">rx1</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> (<span class="ident">_tx2</span>, <span class="ident">rx2</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> (<span class="ident">_tx3</span>, <span class="ident">rx3</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> (<span class="ident">_tx4</span>, <span class="ident">rx4</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> (<span class="ident">tx5</span>, <span class="ident">rx5</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="ident">tx5</span>.<span class="ident">send</span>(<span class="number">4</span>).<span class="ident">unwrap</span>(); <span class="macro">select</span><span class="macro">!</span> { <span class="ident">_foo</span> <span class="op">=</span> <span class="ident">rx1</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">panic</span><span class="macro">!</span>(<span class="string">"1"</span>) }, <span class="ident">_foo</span> <span class="op">=</span> <span class="ident">rx2</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">panic</span><span class="macro">!</span>(<span class="string">"2"</span>) }, <span class="ident">_foo</span> <span class="op">=</span> <span class="ident">rx3</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">panic</span><span class="macro">!</span>(<span class="string">"3"</span>) }, <span class="ident">_foo</span> <span class="op">=</span> <span class="ident">rx4</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">panic</span><span class="macro">!</span>(<span class="string">"4"</span>) }, <span class="ident">foo</span> <span class="op">=</span> <span class="ident">rx5</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">foo</span>.<span class="ident">unwrap</span>(), <span class="number">4</span>); } } } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">closed</span>() { <span class="kw">let</span> (<span class="ident">_tx1</span>, <span class="ident">rx1</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> (<span class="ident">tx2</span>, <span class="ident">rx2</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="ident">drop</span>(<span class="ident">tx2</span>); <span class="macro">select</span><span class="macro">!</span> { <span class="ident">_a1</span> <span class="op">=</span> <span class="ident">rx1</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">panic</span><span class="macro">!</span>() }, <span class="ident">a2</span> <span class="op">=</span> <span class="ident">rx2</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">a2</span>.<span class="ident">is_err</span>()); } } } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">unblocks</span>() { <span class="kw">let</span> (<span class="ident">tx1</span>, <span class="ident">rx1</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> (<span class="ident">_tx2</span>, <span class="ident">rx2</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> (<span class="ident">tx3</span>, <span class="ident">rx3</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> <span class="ident">_t</span> <span class="op">=</span> <span class="ident">thread</span>::<span class="ident">spawn</span>(<span class="kw">move</span><span class="op">||</span> { <span class="kw">for</span> _ <span class="kw">in</span> <span class="number">0</span>..<span class="number">20</span> { <span class="ident">thread</span>::<span class="ident">yield_now</span>(); } <span class="ident">tx1</span>.<span class="ident">send</span>(<span class="number">1</span>).<span class="ident">unwrap</span>(); <span class="ident">rx3</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(); <span class="kw">for</span> _ <span class="kw">in</span> <span class="number">0</span>..<span class="number">20</span> { <span class="ident">thread</span>::<span class="ident">yield_now</span>(); } }); <span class="macro">select</span><span class="macro">!</span> { <span class="ident">a</span> <span class="op">=</span> <span class="ident">rx1</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">a</span>.<span class="ident">unwrap</span>(), <span class="number">1</span>); }, <span class="ident">_b</span> <span class="op">=</span> <span class="ident">rx2</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">panic</span><span class="macro">!</span>() } } <span class="ident">tx3</span>.<span class="ident">send</span>(<span class="number">1</span>).<span class="ident">unwrap</span>(); <span class="macro">select</span><span class="macro">!</span> { <span class="ident">a</span> <span class="op">=</span> <span class="ident">rx1</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">a</span>.<span class="ident">is_err</span>()) }, <span class="ident">_b</span> <span class="op">=</span> <span class="ident">rx2</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">panic</span><span class="macro">!</span>() } } } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">both_ready</span>() { <span class="kw">let</span> (<span class="ident">tx1</span>, <span class="ident">rx1</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> (<span class="ident">tx2</span>, <span class="ident">rx2</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> (<span class="ident">tx3</span>, <span class="ident">rx3</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span>()<span class="op">></span>(); <span class="kw">let</span> <span class="ident">_t</span> <span class="op">=</span> <span class="ident">thread</span>::<span class="ident">spawn</span>(<span class="kw">move</span><span class="op">||</span> { <span class="kw">for</span> _ <span class="kw">in</span> <span class="number">0</span>..<span class="number">20</span> { <span class="ident">thread</span>::<span class="ident">yield_now</span>(); } <span class="ident">tx1</span>.<span class="ident">send</span>(<span class="number">1</span>).<span class="ident">unwrap</span>(); <span class="ident">tx2</span>.<span class="ident">send</span>(<span class="number">2</span>).<span class="ident">unwrap</span>(); <span class="ident">rx3</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(); }); <span class="macro">select</span><span class="macro">!</span> { <span class="ident">a</span> <span class="op">=</span> <span class="ident">rx1</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">a</span>.<span class="ident">unwrap</span>(), <span class="number">1</span>); }, <span class="ident">a</span> <span class="op">=</span> <span class="ident">rx2</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">a</span>.<span class="ident">unwrap</span>(), <span class="number">2</span>); } } <span class="macro">select</span><span class="macro">!</span> { <span class="ident">a</span> <span class="op">=</span> <span class="ident">rx1</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">a</span>.<span class="ident">unwrap</span>(), <span class="number">1</span>); }, <span class="ident">a</span> <span class="op">=</span> <span class="ident">rx2</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">a</span>.<span class="ident">unwrap</span>(), <span class="number">2</span>); } } <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">rx1</span>.<span class="ident">try_recv</span>(), <span class="prelude-val">Err</span>(<span class="ident">TryRecvError</span>::<span class="ident">Empty</span>)); <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">rx2</span>.<span class="ident">try_recv</span>(), <span class="prelude-val">Err</span>(<span class="ident">TryRecvError</span>::<span class="ident">Empty</span>)); <span class="ident">tx3</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">stress</span>() { <span class="kw">const</span> <span class="ident">AMT</span>: <span class="ident">i32</span> <span class="op">=</span> <span class="number">10000</span>; <span class="kw">let</span> (<span class="ident">tx1</span>, <span class="ident">rx1</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> (<span class="ident">tx2</span>, <span class="ident">rx2</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> (<span class="ident">tx3</span>, <span class="ident">rx3</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span>()<span class="op">></span>(); <span class="kw">let</span> <span class="ident">_t</span> <span class="op">=</span> <span class="ident">thread</span>::<span class="ident">spawn</span>(<span class="kw">move</span><span class="op">||</span> { <span class="kw">for</span> <span class="ident">i</span> <span class="kw">in</span> <span class="number">0</span>..<span class="ident">AMT</span> { <span class="kw">if</span> <span class="ident">i</span> <span class="op">%</span> <span class="number">2</span> <span class="op">==</span> <span class="number">0</span> { <span class="ident">tx1</span>.<span class="ident">send</span>(<span class="ident">i</span>).<span class="ident">unwrap</span>(); } <span class="kw">else</span> { <span class="ident">tx2</span>.<span class="ident">send</span>(<span class="ident">i</span>).<span class="ident">unwrap</span>(); } <span class="ident">rx3</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(); } }); <span class="kw">for</span> <span class="ident">i</span> <span class="kw">in</span> <span class="number">0</span>..<span class="ident">AMT</span> { <span class="macro">select</span><span class="macro">!</span> { <span class="ident">i1</span> <span class="op">=</span> <span class="ident">rx1</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">i</span> <span class="op">%</span> <span class="number">2</span> <span class="op">==</span> <span class="number">0</span> <span class="op">&&</span> <span class="ident">i</span> <span class="op">==</span> <span class="ident">i1</span>.<span class="ident">unwrap</span>()); }, <span class="ident">i2</span> <span class="op">=</span> <span class="ident">rx2</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">assert</span><span class="macro">!</span>(<span class="ident">i</span> <span class="op">%</span> <span class="number">2</span> <span class="op">==</span> <span class="number">1</span> <span class="op">&&</span> <span class="ident">i</span> <span class="op">==</span> <span class="ident">i2</span>.<span class="ident">unwrap</span>()); } } <span class="ident">tx3</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); } } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">cloning</span>() { <span class="kw">let</span> (<span class="ident">tx1</span>, <span class="ident">rx1</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> (<span class="ident">_tx2</span>, <span class="ident">rx2</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> (<span class="ident">tx3</span>, <span class="ident">rx3</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span>()<span class="op">></span>(); <span class="kw">let</span> <span class="ident">_t</span> <span class="op">=</span> <span class="ident">thread</span>::<span class="ident">spawn</span>(<span class="kw">move</span><span class="op">||</span> { <span class="ident">rx3</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(); <span class="ident">tx1</span>.<span class="ident">clone</span>(); <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">rx3</span>.<span class="ident">try_recv</span>(), <span class="prelude-val">Err</span>(<span class="ident">TryRecvError</span>::<span class="ident">Empty</span>)); <span class="ident">tx1</span>.<span class="ident">send</span>(<span class="number">2</span>).<span class="ident">unwrap</span>(); <span class="ident">rx3</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(); }); <span class="ident">tx3</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="macro">select</span><span class="macro">!</span> { <span class="ident">_i1</span> <span class="op">=</span> <span class="ident">rx1</span>.<span class="ident">recv</span>() <span class="op">=></span> {}, <span class="ident">_i2</span> <span class="op">=</span> <span class="ident">rx2</span>.<span class="ident">recv</span>() <span class="op">=></span> <span class="macro">panic</span><span class="macro">!</span>() } <span class="ident">tx3</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">cloning2</span>() { <span class="kw">let</span> (<span class="ident">tx1</span>, <span class="ident">rx1</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> (<span class="ident">_tx2</span>, <span class="ident">rx2</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> (<span class="ident">tx3</span>, <span class="ident">rx3</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span>()<span class="op">></span>(); <span class="kw">let</span> <span class="ident">_t</span> <span class="op">=</span> <span class="ident">thread</span>::<span class="ident">spawn</span>(<span class="kw">move</span><span class="op">||</span> { <span class="ident">rx3</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(); <span class="ident">tx1</span>.<span class="ident">clone</span>(); <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">rx3</span>.<span class="ident">try_recv</span>(), <span class="prelude-val">Err</span>(<span class="ident">TryRecvError</span>::<span class="ident">Empty</span>)); <span class="ident">tx1</span>.<span class="ident">send</span>(<span class="number">2</span>).<span class="ident">unwrap</span>(); <span class="ident">rx3</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(); }); <span class="ident">tx3</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="macro">select</span><span class="macro">!</span> { <span class="ident">_i1</span> <span class="op">=</span> <span class="ident">rx1</span>.<span class="ident">recv</span>() <span class="op">=></span> {}, <span class="ident">_i2</span> <span class="op">=</span> <span class="ident">rx2</span>.<span class="ident">recv</span>() <span class="op">=></span> <span class="macro">panic</span><span class="macro">!</span>() } <span class="ident">tx3</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">cloning3</span>() { <span class="kw">let</span> (<span class="ident">tx1</span>, <span class="ident">rx1</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span>()<span class="op">></span>(); <span class="kw">let</span> (<span class="ident">tx2</span>, <span class="ident">rx2</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span>()<span class="op">></span>(); <span class="kw">let</span> (<span class="ident">tx3</span>, <span class="ident">rx3</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span>()<span class="op">></span>(); <span class="kw">let</span> <span class="ident">_t</span> <span class="op">=</span> <span class="ident">thread</span>::<span class="ident">spawn</span>(<span class="kw">move</span><span class="op">||</span> { <span class="kw">let</span> <span class="ident">s</span> <span class="op">=</span> <span class="ident">Select</span>::<span class="ident">new</span>(); <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">h1</span> <span class="op">=</span> <span class="ident">s</span>.<span class="ident">handle</span>(<span class="kw-2">&</span><span class="ident">rx1</span>); <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">h2</span> <span class="op">=</span> <span class="ident">s</span>.<span class="ident">handle</span>(<span class="kw-2">&</span><span class="ident">rx2</span>); <span class="kw">unsafe</span> { <span class="ident">h2</span>.<span class="ident">add</span>(); } <span class="kw">unsafe</span> { <span class="ident">h1</span>.<span class="ident">add</span>(); } <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">s</span>.<span class="ident">wait</span>(), <span class="ident">h2</span>.<span class="ident">id</span>); <span class="ident">tx3</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); }); <span class="kw">for</span> _ <span class="kw">in</span> <span class="number">0</span>..<span class="number">1000</span> { <span class="ident">thread</span>::<span class="ident">yield_now</span>(); } <span class="ident">drop</span>(<span class="ident">tx1</span>.<span class="ident">clone</span>()); <span class="ident">tx2</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="ident">rx3</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(); } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">preflight1</span>() { <span class="kw">let</span> (<span class="ident">tx</span>, <span class="ident">rx</span>) <span class="op">=</span> <span class="ident">channel</span>(); <span class="ident">tx</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="macro">select</span><span class="macro">!</span> { <span class="ident">_n</span> <span class="op">=</span> <span class="ident">rx</span>.<span class="ident">recv</span>() <span class="op">=></span> {} } } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">preflight2</span>() { <span class="kw">let</span> (<span class="ident">tx</span>, <span class="ident">rx</span>) <span class="op">=</span> <span class="ident">channel</span>(); <span class="ident">tx</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="ident">tx</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="macro">select</span><span class="macro">!</span> { <span class="ident">_n</span> <span class="op">=</span> <span class="ident">rx</span>.<span class="ident">recv</span>() <span class="op">=></span> {} } } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">preflight3</span>() { <span class="kw">let</span> (<span class="ident">tx</span>, <span class="ident">rx</span>) <span class="op">=</span> <span class="ident">channel</span>(); <span class="ident">drop</span>(<span class="ident">tx</span>.<span class="ident">clone</span>()); <span class="ident">tx</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="macro">select</span><span class="macro">!</span> { <span class="ident">_n</span> <span class="op">=</span> <span class="ident">rx</span>.<span class="ident">recv</span>() <span class="op">=></span> {} } } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">preflight4</span>() { <span class="kw">let</span> (<span class="ident">tx</span>, <span class="ident">rx</span>) <span class="op">=</span> <span class="ident">channel</span>(); <span class="ident">tx</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="kw">let</span> <span class="ident">s</span> <span class="op">=</span> <span class="ident">Select</span>::<span class="ident">new</span>(); <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">h</span> <span class="op">=</span> <span class="ident">s</span>.<span class="ident">handle</span>(<span class="kw-2">&</span><span class="ident">rx</span>); <span class="kw">unsafe</span> { <span class="ident">h</span>.<span class="ident">add</span>(); } <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">s</span>.<span class="ident">wait2</span>(<span class="bool-val">false</span>), <span class="ident">h</span>.<span class="ident">id</span>); } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">preflight5</span>() { <span class="kw">let</span> (<span class="ident">tx</span>, <span class="ident">rx</span>) <span class="op">=</span> <span class="ident">channel</span>(); <span class="ident">tx</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="ident">tx</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="kw">let</span> <span class="ident">s</span> <span class="op">=</span> <span class="ident">Select</span>::<span class="ident">new</span>(); <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">h</span> <span class="op">=</span> <span class="ident">s</span>.<span class="ident">handle</span>(<span class="kw-2">&</span><span class="ident">rx</span>); <span class="kw">unsafe</span> { <span class="ident">h</span>.<span class="ident">add</span>(); } <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">s</span>.<span class="ident">wait2</span>(<span class="bool-val">false</span>), <span class="ident">h</span>.<span class="ident">id</span>); } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">preflight6</span>() { <span class="kw">let</span> (<span class="ident">tx</span>, <span class="ident">rx</span>) <span class="op">=</span> <span class="ident">channel</span>(); <span class="ident">drop</span>(<span class="ident">tx</span>.<span class="ident">clone</span>()); <span class="ident">tx</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="kw">let</span> <span class="ident">s</span> <span class="op">=</span> <span class="ident">Select</span>::<span class="ident">new</span>(); <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">h</span> <span class="op">=</span> <span class="ident">s</span>.<span class="ident">handle</span>(<span class="kw-2">&</span><span class="ident">rx</span>); <span class="kw">unsafe</span> { <span class="ident">h</span>.<span class="ident">add</span>(); } <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">s</span>.<span class="ident">wait2</span>(<span class="bool-val">false</span>), <span class="ident">h</span>.<span class="ident">id</span>); } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">preflight7</span>() { <span class="kw">let</span> (<span class="ident">tx</span>, <span class="ident">rx</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span>()<span class="op">></span>(); <span class="ident">drop</span>(<span class="ident">tx</span>); <span class="kw">let</span> <span class="ident">s</span> <span class="op">=</span> <span class="ident">Select</span>::<span class="ident">new</span>(); <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">h</span> <span class="op">=</span> <span class="ident">s</span>.<span class="ident">handle</span>(<span class="kw-2">&</span><span class="ident">rx</span>); <span class="kw">unsafe</span> { <span class="ident">h</span>.<span class="ident">add</span>(); } <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">s</span>.<span class="ident">wait2</span>(<span class="bool-val">false</span>), <span class="ident">h</span>.<span class="ident">id</span>); } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">preflight8</span>() { <span class="kw">let</span> (<span class="ident">tx</span>, <span class="ident">rx</span>) <span class="op">=</span> <span class="ident">channel</span>(); <span class="ident">tx</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="ident">drop</span>(<span class="ident">tx</span>); <span class="ident">rx</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(); <span class="kw">let</span> <span class="ident">s</span> <span class="op">=</span> <span class="ident">Select</span>::<span class="ident">new</span>(); <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">h</span> <span class="op">=</span> <span class="ident">s</span>.<span class="ident">handle</span>(<span class="kw-2">&</span><span class="ident">rx</span>); <span class="kw">unsafe</span> { <span class="ident">h</span>.<span class="ident">add</span>(); } <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">s</span>.<span class="ident">wait2</span>(<span class="bool-val">false</span>), <span class="ident">h</span>.<span class="ident">id</span>); } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">preflight9</span>() { <span class="kw">let</span> (<span class="ident">tx</span>, <span class="ident">rx</span>) <span class="op">=</span> <span class="ident">channel</span>(); <span class="ident">drop</span>(<span class="ident">tx</span>.<span class="ident">clone</span>()); <span class="ident">tx</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="ident">drop</span>(<span class="ident">tx</span>); <span class="ident">rx</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(); <span class="kw">let</span> <span class="ident">s</span> <span class="op">=</span> <span class="ident">Select</span>::<span class="ident">new</span>(); <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">h</span> <span class="op">=</span> <span class="ident">s</span>.<span class="ident">handle</span>(<span class="kw-2">&</span><span class="ident">rx</span>); <span class="kw">unsafe</span> { <span class="ident">h</span>.<span class="ident">add</span>(); } <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">s</span>.<span class="ident">wait2</span>(<span class="bool-val">false</span>), <span class="ident">h</span>.<span class="ident">id</span>); } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">oneshot_data_waiting</span>() { <span class="kw">let</span> (<span class="ident">tx1</span>, <span class="ident">rx1</span>) <span class="op">=</span> <span class="ident">channel</span>(); <span class="kw">let</span> (<span class="ident">tx2</span>, <span class="ident">rx2</span>) <span class="op">=</span> <span class="ident">channel</span>(); <span class="kw">let</span> <span class="ident">_t</span> <span class="op">=</span> <span class="ident">thread</span>::<span class="ident">spawn</span>(<span class="kw">move</span><span class="op">||</span> { <span class="macro">select</span><span class="macro">!</span> { <span class="ident">_n</span> <span class="op">=</span> <span class="ident">rx1</span>.<span class="ident">recv</span>() <span class="op">=></span> {} } <span class="ident">tx2</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); }); <span class="kw">for</span> _ <span class="kw">in</span> <span class="number">0</span>..<span class="number">100</span> { <span class="ident">thread</span>::<span class="ident">yield_now</span>() } <span class="ident">tx1</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="ident">rx2</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(); } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">stream_data_waiting</span>() { <span class="kw">let</span> (<span class="ident">tx1</span>, <span class="ident">rx1</span>) <span class="op">=</span> <span class="ident">channel</span>(); <span class="kw">let</span> (<span class="ident">tx2</span>, <span class="ident">rx2</span>) <span class="op">=</span> <span class="ident">channel</span>(); <span class="ident">tx1</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="ident">tx1</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="ident">rx1</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(); <span class="ident">rx1</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(); <span class="kw">let</span> <span class="ident">_t</span> <span class="op">=</span> <span class="ident">thread</span>::<span class="ident">spawn</span>(<span class="kw">move</span><span class="op">||</span> { <span class="macro">select</span><span class="macro">!</span> { <span class="ident">_n</span> <span class="op">=</span> <span class="ident">rx1</span>.<span class="ident">recv</span>() <span class="op">=></span> {} } <span class="ident">tx2</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); }); <span class="kw">for</span> _ <span class="kw">in</span> <span class="number">0</span>..<span class="number">100</span> { <span class="ident">thread</span>::<span class="ident">yield_now</span>() } <span class="ident">tx1</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="ident">rx2</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(); } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">shared_data_waiting</span>() { <span class="kw">let</span> (<span class="ident">tx1</span>, <span class="ident">rx1</span>) <span class="op">=</span> <span class="ident">channel</span>(); <span class="kw">let</span> (<span class="ident">tx2</span>, <span class="ident">rx2</span>) <span class="op">=</span> <span class="ident">channel</span>(); <span class="ident">drop</span>(<span class="ident">tx1</span>.<span class="ident">clone</span>()); <span class="ident">tx1</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="ident">rx1</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(); <span class="kw">let</span> <span class="ident">_t</span> <span class="op">=</span> <span class="ident">thread</span>::<span class="ident">spawn</span>(<span class="kw">move</span><span class="op">||</span> { <span class="macro">select</span><span class="macro">!</span> { <span class="ident">_n</span> <span class="op">=</span> <span class="ident">rx1</span>.<span class="ident">recv</span>() <span class="op">=></span> {} } <span class="ident">tx2</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); }); <span class="kw">for</span> _ <span class="kw">in</span> <span class="number">0</span>..<span class="number">100</span> { <span class="ident">thread</span>::<span class="ident">yield_now</span>() } <span class="ident">tx1</span>.<span class="ident">send</span>(()).<span class="ident">unwrap</span>(); <span class="ident">rx2</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(); } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">sync1</span>() { <span class="kw">let</span> (<span class="ident">tx</span>, <span class="ident">rx</span>) <span class="op">=</span> <span class="ident">sync_channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(<span class="number">1</span>); <span class="ident">tx</span>.<span class="ident">send</span>(<span class="number">1</span>).<span class="ident">unwrap</span>(); <span class="macro">select</span><span class="macro">!</span> { <span class="ident">n</span> <span class="op">=</span> <span class="ident">rx</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">n</span>.<span class="ident">unwrap</span>(), <span class="number">1</span>); } } } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">sync2</span>() { <span class="kw">let</span> (<span class="ident">tx</span>, <span class="ident">rx</span>) <span class="op">=</span> <span class="ident">sync_channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(<span class="number">0</span>); <span class="kw">let</span> <span class="ident">_t</span> <span class="op">=</span> <span class="ident">thread</span>::<span class="ident">spawn</span>(<span class="kw">move</span><span class="op">||</span> { <span class="kw">for</span> _ <span class="kw">in</span> <span class="number">0</span>..<span class="number">100</span> { <span class="ident">thread</span>::<span class="ident">yield_now</span>() } <span class="ident">tx</span>.<span class="ident">send</span>(<span class="number">1</span>).<span class="ident">unwrap</span>(); }); <span class="macro">select</span><span class="macro">!</span> { <span class="ident">n</span> <span class="op">=</span> <span class="ident">rx</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">n</span>.<span class="ident">unwrap</span>(), <span class="number">1</span>); } } } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">sync3</span>() { <span class="kw">let</span> (<span class="ident">tx1</span>, <span class="ident">rx1</span>) <span class="op">=</span> <span class="ident">sync_channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(<span class="number">0</span>); <span class="kw">let</span> (<span class="ident">tx2</span>, <span class="ident">rx2</span>): (<span class="ident">Sender</span><span class="op"><</span><span class="ident">i32</span><span class="op">></span>, <span class="ident">Receiver</span><span class="op"><</span><span class="ident">i32</span><span class="op">></span>) <span class="op">=</span> <span class="ident">channel</span>(); <span class="kw">let</span> <span class="ident">_t</span> <span class="op">=</span> <span class="ident">thread</span>::<span class="ident">spawn</span>(<span class="kw">move</span><span class="op">||</span> { <span class="ident">tx1</span>.<span class="ident">send</span>(<span class="number">1</span>).<span class="ident">unwrap</span>(); }); <span class="kw">let</span> <span class="ident">_t</span> <span class="op">=</span> <span class="ident">thread</span>::<span class="ident">spawn</span>(<span class="kw">move</span><span class="op">||</span> { <span class="ident">tx2</span>.<span class="ident">send</span>(<span class="number">2</span>).<span class="ident">unwrap</span>(); }); <span class="macro">select</span><span class="macro">!</span> { <span class="ident">n</span> <span class="op">=</span> <span class="ident">rx1</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="kw">let</span> <span class="ident">n</span> <span class="op">=</span> <span class="ident">n</span>.<span class="ident">unwrap</span>(); <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">n</span>, <span class="number">1</span>); <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">rx2</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(), <span class="number">2</span>); }, <span class="ident">n</span> <span class="op">=</span> <span class="ident">rx2</span>.<span class="ident">recv</span>() <span class="op">=></span> { <span class="kw">let</span> <span class="ident">n</span> <span class="op">=</span> <span class="ident">n</span>.<span class="ident">unwrap</span>(); <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">n</span>, <span class="number">2</span>); <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="ident">rx1</span>.<span class="ident">recv</span>().<span class="ident">unwrap</span>(), <span class="number">1</span>); } } } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">fmt_debug_select</span>() { <span class="kw">let</span> <span class="ident">sel</span> <span class="op">=</span> <span class="ident">Select</span>::<span class="ident">new</span>(); <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="macro">format</span><span class="macro">!</span>(<span class="string">"{:?}"</span>, <span class="ident">sel</span>), <span class="string">"Select { .. }"</span>); } <span class="attribute">#[<span class="ident">test</span>]</span> <span class="kw">fn</span> <span class="ident">fmt_debug_handle</span>() { <span class="kw">let</span> (_, <span class="ident">rx</span>) <span class="op">=</span> <span class="ident">channel</span>::<span class="op"><</span><span class="ident">i32</span><span class="op">></span>(); <span class="kw">let</span> <span class="ident">sel</span> <span class="op">=</span> <span class="ident">Select</span>::<span class="ident">new</span>(); <span class="kw">let</span> <span class="ident">handle</span> <span class="op">=</span> <span class="ident">sel</span>.<span class="ident">handle</span>(<span class="kw-2">&</span><span class="ident">rx</span>); <span class="macro">assert_eq</span><span class="macro">!</span>(<span class="macro">format</span><span class="macro">!</span>(<span class="string">"{:?}"</span>, <span class="ident">handle</span>), <span class="string">"Handle { .. }"</span>); } } </pre> </section> <section id='search' class="content hidden"></section> <section class="footer"></section> <aside id="help" class="hidden"> <div> <h1 class="hidden">Help</h1> <div class="shortcuts"> <h2>Keyboard Shortcuts</h2> <dl> <dt>?</dt> <dd>Show this help dialog</dd> <dt>S</dt> <dd>Focus the search field</dd> <dt>⇤</dt> <dd>Move up in search results</dd> <dt>⇥</dt> <dd>Move down in search results</dd> <dt>⏎</dt> <dd>Go to active search result</dd> <dt>+</dt> <dd>Collapse/expand all sections</dd> </dl> </div> <div class="infos"> <h2>Search Tricks</h2> <p> Prefix searches with a type followed by a colon (e.g. <code>fn:</code>) to restrict the search to a given type. </p> <p> Accepted types are: <code>fn</code>, <code>mod</code>, <code>struct</code>, <code>enum</code>, <code>trait</code>, <code>type</code>, <code>macro</code>, and <code>const</code>. </p> <p> Search functions by type signature (e.g. <code>vec -> usize</code> or <code>* -> vec</code>) </p> </div> </div> </aside> <script> window.rootPath = "../../../../"; 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