<?xml version="1.0" encoding="iso-8859-1"?>
<?xml-stylesheet type="text/css" href="../../styles.css" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
<head>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />
<title>Logtalk control construct: ::/2</title>
<link rel="stylesheet" href="../../styles.css" type="text/css" />
</head>
<body>
<div class="navtop">
<a href="../../index.html">contents</a> > <a href="../index.html">reference manual</a> > <a href="../index.html#constructs">control constructs</a>
</div>
<h2><code>::/2</code></h2>
<h4>Description</h4>
<blockquote>
<pre>Object::Predicate
(Object1, Object2, ...)::Predicate
(Object1; Object2; ...)::Predicate
Object::(Predicate1, Predicate2, ...)
Object::(Predicate1; Predicate2; ...)</pre>
<p>
Sends a message to an object. The message argument must match a public predicate of the receiver object. We can also send the same message to a set of objects or a set of messages to the same object. The "<code>,</code>" and "<code>;</code>" in the list have the usual Prolog meaning.
</p>
</blockquote>
<h4>Template and modes</h4>
<blockquote>
<pre>+receivers::+messages</pre>
</blockquote>
<h4>Errors</h4>
<blockquote>
<dl>
<dt>Either Object or Predicate is a variable:</dt>
<dd><code>instantiation_error</code></dd>
<dt>Predicate is declared private:</dt>
<dd><code>permission_error(access, private_predicate, Predicate)</code></dd>
<dt>Predicate is declared protected:</dt>
<dd><code>permission_error(access, protected_predicate, Predicate)</code></dd>
<dt>Predicate is not declared:</dt>
<dd><code>existence_error(predicate_declaration, Predicate)</code></dd>
<dt>Object does not exist:</dt>
<dd><code>existence_error(object, Object)</code></dd>
</dl>
</blockquote>
<h4>Examples</h4>
<blockquote>
<pre>| ?- list::member(X, [1, 2, 3]).</pre>
</blockquote>
<div class="navbottom">
<a href="../methods/after3.html">previous</a> | <a href="../../glossary.html">glossary</a> | <a href="to_self1.html">next</a>
</div>
<div class="copyright">
Copyright © <a href="mailto:pmoura@logtalk.org">Paulo Moura</a> — <a href="http://www.logtalk.org">Logtalk.org</a>
</div>
<div class="footer">
<p><span class="bleft"><a href="http://validator.w3.org/check/referer">XHTML</a> + <a href="http://jigsaw.w3.org/css-validator/check/referer">CSS</a></span><span class="bright">Last updated on: December 23, 2003</span></p>
</div>
</body>
</html>