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<html><title>Programming Ruby: The Pragmatic Programmer's Guide</title><head><meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"><STYLE TYPE="text/css"><!--
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</STYLE><table bgcolor="#a03030" cellpadding="3" border="0" cellspacing="0"><tr><td colspan="3"><table bgcolor="#902020" cellpadding="20"><tr><td><h1 class="header">Programming Ruby</h1><h3 class="subheader">The Pragmatic Programmer's Guide</h3></td></tr></table></td></tr><tr><td width="33%" align="left"><a class="subheader" href="ref_c_time.html">Previous <</a></td><td width="33%" align="center" valign="middle"><a class="subheader" href="builtins.html">Contents ^</a><br></td><td width="33%" align="right"><a class="subheader" href="ref_m_comparable.html">Next ></a><br></td></tr></table></head><body bgcolor="white">
<!--
Copyright (c) 2001 by Addison Wesley Longman. This
material may be distributed only subject to the terms and
conditions set forth in the Open Publication License, v1.0 or
later (the latest version is presently available at
http://www.opencontent.org/openpub/).
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<table><tr><td height="20"><img src="dot.gif" width="1" height="20"></td></tr></table><table border="0" width="100%" bgcolor="660066" cellpadding="10"><tr><td valign="center"><font color="white" size="7">class TrueClass</font></td><td><table border="0"><tr><td><font color="white">
Parent:
</font></td><td><font color="white">Object</font></td></tr><tr><td><font color="white">
Version:
</font></td><td><font color="white">
1.6
</font></td></tr></table></td></tr></table><p></p><H3>Index:</H3><a href="#_et"><i>&</i></a> <a href="#_up"><i>^</i></a> <a href="#_ba"><i>|</i></a> <p></p><hr>
The global value <code>true</code> is the only instance of class
<code>TrueClass</code> and represents a logically true value in boolean
expressions. The class provides operators allowing <code>true</code>
to be used in logical expressions.
<P></P>
<table border="0" width="100%" cellpadding="10"><tr><td valign="center" colspan="2" bgcolor="990066"><font color="white" size="6">instance methods
</font></td></tr><tr><td valign="center" bgcolor="#ff9999"><font size="4"><a name="_et"><b>&</b></a></font></td><td bgcolor="#ffaaaa">
<code>true</code> & <i>anObject</i>
-> <i>anObject</i>
</td></tr><td></td><td>
<P></P>
And---Returns <code>false</code> if <i>anObject</i> is <code>nil</code> or
<code>false</code>, <code>true</code> otherwise.
<P></P>
</td><tr><td valign="center" bgcolor="#ff9999"><font size="4"><a name="_up"><b>^</b></a></font></td><td bgcolor="#ffaaaa">
<code>true</code> ^ <i>anObject</i>
-> !<i>anObject</i>
</td></tr><td></td><td>
<P></P>
Exclusive Or---Returns <code>true</code> if
<i>anObject</i> is <code>nil</code> or <code>false</code>,
<code>false</code> otherwise.
<P></P>
</td><tr><td valign="center" bgcolor="#ff9999"><font size="4"><a name="_ba"><b>|</b></a></font></td><td bgcolor="#ffaaaa">
<code>true</code> | <i>anObject</i>
-> <code>true</code>
</td></tr><td></td><td>
<P></P>
Or---Returns <code>true</code>. As <i>anObject</i> is an
argument to a method call, it is always evaluated; there is no
short-circuit evaluation in this case.
<P></P>
<table bgcolor="#fff0f0" cellspacing="0" border="0" cellpadding="3" width="400"><tr><td><pre>
true | puts("or")
true || puts("logical or")
</pre></td></tr></table>
<em>produces:</em>
<table bgcolor="#fff0f0" cellspacing="0" border="0" cellpadding="3" width="400"><tr><td><pre>
or
</pre></td></tr></table>
<P></P>
</td></table>
<P></P>
<p></p><hr><table bgcolor="#a03030" cellpadding="10" border="0" cellspacing="0"><tr><td width="33%" align="left"><a class="subheader" href="ref_c_time.html">Previous <</a></td><td width="33%" align="center" valign="middle"><a class="subheader" href="builtins.html">Contents ^</a><br></td><td width="33%" align="right"><a class="subheader" href="ref_m_comparable.html">Next ></a><br></td></tr></table><p></p><font size="-1">Extracted from the book "Programming Ruby -
The Pragmatic Programmer's Guide"</font><br><font size="-3">
Copyright
©
2000 Addison Wesley Longman, Inc. Released under the terms of the
<a href="http://www.opencontent.org/openpub/">Open Publication License</a> V1.0.
<br>
This reference is available for
<a href="http://www.pragmaticprogrammer.com/ruby/downloads/book.html">download</a>.
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