New issue from Dietmar Kühl: Missing rvalue reference qualification for task_scheduler::ts-sender::connect()

Author: dietmarkuehl

xml/issue4342.xml

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+<?xml version='1.0' encoding='utf-8' standalone='no'?>
+<!DOCTYPE issue SYSTEM "lwg-issue.dtd">
+
+<issue num="4342" status="New">
+<title>Missing rvalue reference qualification for <code>task_scheduler::ts-sender::connect()</code></title>
+<section><sref ref="[exec.task.scheduler]"/></section>
+<submitter>Dietmar Kühl</submitter>
+<date>01 Sep 2025</date>
+<priority>99</priority>
+
+<discussion>
+<p>
+The result of <code>schedule(sched)</code> for a scheduler
+<code>sched</code> is only required to be movable. An object of
+this type may need to be forwarded to an operation state constructor
+by <code>task_scheduler::<i>ts-sender</i>::connect</code>. Thus,
+this function should be qualified with an rvalue reference.
+</p>
+</discussion>
+
+<resolution>
+<p>
+Add an rvalue qualifier to the declaration of <code>connect</code> in <sref ref="[exec.task.scheduler]"/> paragraph 8:
+<blockquote>
+<pre>
+namespace std::execution {
+  class task_scheduler::ts-sender {     // exposition only
+  public:
+    using sender_concept = sender_t;
+
+    template&lt;receiver Rcvr&gt;
+      <i>state</i>&lt;Rcvr&gt; connect(Rcvr&amp;&amp; rcvr)<ins> &amp;&amp;</ins>;
+  };
+}
+</pre>
+</blockquote>
+</p>
+<p>
+In the specification in <sref ref="[exec.task.scheduler]"/> paragraph 10 add an rvalue qualifier to <code>connect</code>:
+<blockquote>
+<pre>
+template&lt;receiver Rcvr&gt;
+  <i>state</i>&lt;Rcvr&gt; connect(Rcvr&amp;&amp; rcvr)<ins> &amp;&amp;</ins>;
+</pre>
+<p>-10- <i>Effects</i>: Let <i>r</i> be an object of a type that
+models receiver and whose completion handlers result in invoking
+the corresponding completion handlers of <code>rcvr</code> or copy thereof.
+Returns an object of type <code><i>state</i>&lt;Rcvr&gt;</code> containing an operation state
+object initialized with <code>connect(<i>SENDER</i>(*this), std::move(<i>r</i>))</code>.
+</p>
+</blockquote>
+</p>
+</resolution>
+
+</issue>