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<div class="top-left">Logtalk reference manual</div>
<div class="top-right">Built-in predicate: threaded_call/2</div>
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<h2 class="codenp">threaded_call/2<span id="builtins_threaded_call2"/></h2>
<h4>Description</h4>
<pre>threaded_call(Goal, Options)
threaded_call((Goal1, Goal2, ...), Options)
threaded_call((Goal1; Goal2; ...), Options)</pre>
<p>
Prove <code>Goal</code> using a new thread. By default, the proof is done asynchronously. The argument can be a message sending. The result (success, failure, or exception) is sent back to the thread of the object containing the call (<em>this</em>). The option <code>noreply</code> may be used when no reply with the proof results is necessary. The option <code>atomic</code> may be used if the goal has side-effects such as dynamic database updates or input-output operations; this option is only safe if the side-effects are confined to the object where the goal is proved (or to the object receiving the asynchronous message).
</p>
<p>
When the argument is a <em>conjunction</em> of goals, the call is equivalent the conjunction of calls of the individual goals. However, when the argument is a <em>disjunction</em> of goals, the call is equivalent to the <em>competing</em> calls of the individual goals: when one of the goals complete, the other ones are aborted (i.e. their threads are terminated). In this case, the corresponding <code>threaded_exit/1-2</code> goal <strong>must</strong> match all the goals in the disjunction. This is useful when you have a set of different methods to solve a problem without knowing a priori which one will lead to the fastest result.
</p>
<h4>Template and modes</h4>
<pre>threaded_call(+callable, +list)</pre>
<h4>Examples</h4>
<dl>
<dt>Prove <code>Goal</code> asynchronously in a new thread:</dt>
<dd><code>threaded_call(Goal, Options)</code></dd>
<dt>Send an asynchronous message to <em>self</em>:</dt>
<dd><code>threaded_call(::Message, Options)</code></dd>
<dt>Send an asynchronous message to an object:</dt>
<dd><code>threaded_call(Object::Message, Options)</code></dd>
</dl>
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<span>Copyright © <a href="mailto:pmoura@logtalk.org">Paulo Moura</a> — <a href="http://logtalk.org">Logtalk.org</a></span><br/>
<span>Last updated on: October 26, 2006</span>
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