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It is provided "as is" without express or implied warranty. -- --><Head><Title>logical_and<T></Title><!-- Generated by htmldoc --></HEAD><BODY TEXT="#000000" LINK="#006600" ALINK="#003300" VLINK="#7C7F87" BGCOLOR="#FFFFFF"><A HREF="/"><IMG SRC="/images/common/sgilogo_small.gif" ALT="SGI Logo" WIDTH="80" HEIGHT="72" BORDER="0"></A><P><!--end header--><BR Clear><H1>logical_and<T></H1><Table CellPadding=0 CellSpacing=0 width=100%><TR><TD Align=left><Img src = "functors.gif" Alt="" WIDTH = "194" HEIGHT = "38" ></TD><TD Align=right><Img src = "type.gif" Alt="" WIDTH = "194" HEIGHT = "38" ></TD></TR><TR><TD Align=left VAlign=top><b>Category</b>: functors</TD><TD Align=right VAlign=top><b>Component type</b>: type</TD></TR></Table><h3>Description</h3><tt>Logical_and<T></tt> is a <A href="functors.html">function object</A>; specifically, it is an <A href="AdaptableBinaryPredicate.html">Adaptable Binary Predicate</A>, which means it is a function object that tests the truth or falsehood of some condition.If <tt>f</tt> is an object of class <tt>logical_and<T></tt>and <tt>x</tt> and <tt>y</tt> are objects of class <tt>T</tt> (where <tt>T</tt> is convertibleto <tt>bool</tt>) then <tt>f(x,y)</tt> returns true if and only if both <tt>x</tt> and<tt>y</tt> are <tt>true</tt>. <A href="#1">[1]</A><h3>Example</h3>Finds the first element in a list that lies in the range from 1 to 10.<pre><A href="List.html">list</A><int> L;...<A href="List.html">list</A><int>::iterator in_range = <A href="find_if.html">find_if</A>(L.begin(), L.end(), <A href="binary_compose.html">compose2</A>(logical_and<bool>(), <A href="binder2nd.html">bind2nd</A>(<A href="greater_equal.html">greater_equal</A><int>(), 1), <A href="binder2nd.html">bind2nd</A>(<A href="less_equal.html">less_equal</A><int>(), 10)));assert(in_range == L.end() || (*in_range >= 1 && *in_range <= 10));</pre><h3>Definition</h3>Defined in the standard header <A href="functional">functional</A>, and in the nonstandardbackward-compatibility header <A href="function.h">function.h</A>.<h3>Template parameters</h3><Table border><TR><TH>Parameter</TH><TH>Description</TH><TH>Default</TH></TR><TR><TD VAlign=top><tt>T</tt></TD><TD VAlign=top>The type of <tt>logical_and</tt>'s arguments</TD><TD VAlign=top> </TD></tr></table><h3>Model of</h3><A href="AdaptableBinaryPredicate.html">Adaptable Binary Predicate</A>, <A href="DefaultConstructible.html">DefaultConstructible</A><h3>Type requirements</h3><tt>T</tt> must be convertible to <tt>bool</tt>.<h3>Public base classes</h3><tt><A href="binary_function.html">binary_function</A><T, T, bool></tt><h3>Members</h3><Table border><TR><TH>Member</TH><TH>Where defined</TH><TH>Description</TH></TR><TR><TD VAlign=top><tt>first_argument_type</tt></TD><TD VAlign=top> <A href="AdaptableBinaryFunction.html">Adaptable Binary Function</A></TD><TD VAlign=top>The type of the first argument: <tt>T</tt></TD></TR><TR><TD VAlign=top><tt>second_argument_type</tt></TD><TD VAlign=top> <A href="AdaptableBinaryFunction.html">Adaptable Binary Function</A></TD><TD VAlign=top>The type of the second argument: <tt>T</tt></TD></TR><TR><TD VAlign=top><tt>result_type</tt></TD><TD VAlign=top> <A href="AdaptableBinaryFunction.html">Adaptable Binary Function</A></TD><TD VAlign=top>The type of the result: <tt>bool</tt></TD></TR><TR><TD VAlign=top><tt>bool operator()(const T& x, const T& y) const</tt></TD><TD VAlign=top> <A href="BinaryFunction.html">Binary Function</A></TD><TD VAlign=top>Function call operator. The return value is <tt>x && y</tt>.</TD></TR><TR><TD VAlign=top><tt>logical_and()</tt></TD><TD VAlign=top> <A href="DefaultConstructible.html">Default Constructible</A></TD><TD VAlign=top>The default constructor.</TD></tr></table><h3>New members</h3>All of <tt>logical_and</tt>'s members are defined in the <A href="AdaptableBinaryFunction.html">Adaptable Binary Function</A> and <A href="DefaultConstructible.html">Default Constructible</A>requirements. <tt>Logical_and</tt> does not introduce any new members.<h3>Notes</h3><P><A name="1">[1]</A><tt>Logical_and</tt> and <tt><A href="logical_or.html">logical_or</A></tt> are not very useful by themselves.They are mainly useful because, when combined with the function objectadaptor <tt><A href="binary_compose.html">binary_compose</A></tt>, they perform logical operations on otherfunction objects.<h3>See also</h3>The <A href="functors.html">function object overview</A>, <tt><A href="logical_or.html">logical_or</A></tt>, <tt><A href="logical_not.html">logical_not</A></tt>.<!-- start footer --><!-- Footer Begins --><STYLE TYPE="text/css"><!--TD.footer, TD.footer A{ font-family: Arial, helvetica, sans-serif; font-size: 8pt;}A.home {font-family: Arial, helvetica, sans-serif;}--></STYLE><P><A CLASS="home" HREF="index.html">STL Home</A><P><TABLE WIDTH="600" CELLPADDING="0" CELLPADDING="0" BORDER="0"> <TR> <TD ALIGN="RIGHT" CLASS="footer"><A HREF="/company_info/terms.html" TARGET="_top">terms of use</A> | <A HREF="/company_info/privacy.html" TARGET="_top">privacy policy</A></TD> <TD ALIGN="CENTER" CLASS="footer"> | </TD> <TD ALIGN="LEFT" CLASS="footer"><A HREF="/cgi-bin/feedback/" TARGET="_top">contact us</A></TD> </TR><TR> <TD ALIGN="RIGHT" CLASS="footer">Copyright © 1993-2003 Silicon Graphics, Inc. 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