<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
    "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">

<head>
	<meta http-equiv="content-type" content="application/xml+xhtml; charset=utf-8" />
	<title>Logtalk entity directive: object/1-5</title>
	<link rel="stylesheet" href="../../screen.css" type="text/css" media="screen"/>
	<link rel="stylesheet" href="../../print.css" type="text/css" media="print"/>
</head>

<body>

<div class="top-left">Logtalk reference manual</div> 
<div class="top-right">Entity directive: object/1-5</div>
<div class="bottom-left"><span class="page"/></div> 
<div class="bottom-right"><span class="page"/></div>
<div class="navtop"><a href="../../index.html">contents</a> &gt; <a href="../index.html">reference manual</a> &gt; <a href="../index.html#directives">directives</a></div>

<h2 id="directives_object1_5" class="codenp">object/1-5</h2>

<h4>Description</h4>

<p>
<em>Stand-alone objects (prototypes)</em>
</p>
<pre>object(Object)

object(Object,
    implements(Protocols))

object(Object,
    imports(Categories))

object(Object,
    implements(Protocols),
    imports(Categories))</pre>
<p>
<em>Prototype extensions</em>
</p>
<pre>object(Object,
    extends(Objects))

object(Object,
    implements(Protocols),
    extends(Objects))

object(Object,
    imports(Categories),
    extends(Objects))

object(Object,
    implements(Protocols),
    imports(Categories),
    extends(Objects))</pre>
<p>
	<em>Class instances</em>
</p>
<pre>object(Object,
    instantiates(Classes))

object(Object,
    implements(Protocols),
    instantiates(Classes))

object(Object,
    imports(Categories),
    instantiates(Classes))

object(Object,
    implements(Protocols),
    imports(Categories),
    instantiates(Classes))</pre>
<p>
	<em>Classes</em>
</p>
<pre>object(Object,
    specializes(Classes))

object(Object,
    implements(Protocols),
    specializes(Classes))

object(Object,
    imports(Categories),
    specializes(Classes))

object(Object,
    implements(Protocols),
    imports(Categories),
    specializes(Classes))</pre>
<p>
<em>Classes with metaclasses</em>
</p>
<pre>object(Object,
    instantiates(Classes),
    specializes(Classes))

object(Object,
    implements(Protocols),
    instantiates(Classes),
    specializes(Classes))

object(Object,
    imports(Categories),
    instantiates(Classes),
    specializes(Classes))

object(Object,
    implements(Protocols),
    imports(Categories),
    instantiates(Classes),
    specializes(Classes))</pre>
<p>
Starting object directive.
</p>

<h4>Template and modes</h4>

<p>
<em>Stand-alone objects (prototypes)</em>
</p>
<pre>object(+object_identifier)

object(+object_identifier,
    implements(+implemented_protocols))

object(+object_identifier,
    imports(+imported_categories))

object(+object_identifier,
    implements(+implemented_protocols),
    imports(+imported_categories))</pre>
<p>
<em>Prototype extensions</em>
</p>
<pre>object(+object_identifier,
    extends(+extended_objects))

object(+object_identifier,
    implements(+implemented_protocols),
    extends(+extended_objects))

object(+object_identifier,
    imports(+imported_categories),
    extends(+extended_objects))

object(+object_identifier,
    implements(+implemented_protocols),
    imports(+imported_categories),
    extends(+extended_objects))</pre>
<p>
<em>Class instances</em>
</p>
<pre>object(+object_identifier,
    instantiates(+instantiated_objects))

object(+object_identifier,
    implements(+implemented_protocols),
    instantiates(+instantiated_objects))

object(+object_identifier,
    imports(+imported_categories),
    instantiates(+instantiated_objects))

object(+object_identifier,
    implements(+implemented_protocols),
    imports(+imported_categories),
    instantiates(+instantiated_objects))</pre>
<p>
<em>Classes</em>
</p>
<pre>object(+object_identifier,
    specializes(+specialized_objects))

object(+object_identifier,
    implements(+implemented_protocols),
    specializes(+specialized_objects))

object(+object_identifier,
    imports(+imported_categories),
    specializes(+specialized_objects))

object(+object_identifier,
    implements(+implemented_protocols),
    imports(+imported_categories),
    specializes(+specialized_objects))</pre>
<p>
	<em>Class with metaclasses</em>
</p>
<pre>object(+object_identifier,
    instantiates(+instantiated_objects),
    specializes(+specialized_objects))

object(+object_identifier,
    implements(+implemented_protocols),
    instantiates(+instantiated_objects),
    specializes(+specialized_objects))

object(+object_identifier,
    imports(+imported_categories),
    instantiates(+instantiated_objects),
    specializes(+specialized_objects))

object(+object_identifier,
    implements(+implemented_protocols),
    imports(+imported_categories),
    instantiates(+instantiated_objects),
    specializes(+specialized_objects))</pre>


<h4>Examples</h4>

<pre>:- object(list).

:- object(list,
    implements(listp)).

:- object(list,
    extends(compound)).

:- object(list,
    implements(listp),
    extends(compound)).

:- object(object,
    imports(initialization),
    instantiates(class)).

:- object(abstract_class,
    instantiates(class),
    specializes(object)).

:- object(agent,
    imports(private::attributes)).</pre>

<div class="footer">
	<div class="copyright">
		<span>Copyright &copy; <a href="mailto:pmoura@logtalk.org">Paulo Moura</a> &mdash; <a href="http://logtalk.org">Logtalk.org</a></span><br/>	
		<span>Last updated on: December 11, 2006</span>
	</div>
	<div class="navbottom">
		<span><a href="initialization1.html">previous</a> | <a href="../../glossary.html">glossary</a> | <a href="protocol1_2.html">next</a></span><br/>
		<span><a href="http://validator.w3.org/check/referer">XHTML</a> + <a href="http://jigsaw.w3.org/css-validator/check/referer">CSS</a></span>
	</div>
</div>

</body>

</html>