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It is provided "as is" without express or implied warranty. -- --><Head><Title>binary_compose<AdaptableBinaryFunction,AdaptableUnaryFunction1,AdaptableUnaryFunction2></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>binary_compose<AdaptableBinaryFunction,AdaptableUnaryFunction1,AdaptableUnaryFunction2></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><Img src = "adaptors.gif" Alt="" WIDTH = "194" HEIGHT = "38" ></TD><TD Align=right></TD></TR><TR><TD Align=left VAlign=top><b>Categories</b>: functors, adaptors</TD><TD Align=right VAlign=top><b>Component type</b>: type</TD></TR></Table><h3>Description</h3><tt>Binary_compose</tt> is a <A href="functors.html">function object</A> adaptor. If <tt>f</tt> is an <A href="AdaptableBinaryFunction.html">Adaptable Binary Function</A> and <tt>g1</tt> and <tt>g2</tt> are both<A href="AdaptableUnaryFunction.html">Adaptable Unary Functions</A>, and if <tt>g1</tt>'s and <tt>g2</tt>'s return typesare convertible to <tt>f</tt>'s argument types, then <tt>binary_compose</tt> can be used to create a function object <tt>h</tt> such that <tt>h(x)</tt> is the same as <tt>f(g1(x), g2(x))</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(), compose2(<A href="logical_and.html">logical_and</A><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><P>Computes <tt>sin(x)/(x + DBL_MIN)</tt> for each element of a range.<pre><A href="transform.html">transform</A>(first, last, first, compose2(<A href="divides.html">divides</A><double>(), <A href="ptr_fun.html">ptr_fun</A>(sin), <A href="binder2nd.html">bind2nd</A>(<A href="plus.html">plus</A><double>(), DBL_MIN)));</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>. The <tt>binary_compose</tt>class is an SGI extension; it is not part of the C++ standard.<h3>Template parameters</h3><Table border><TR><TH>Parameter</TH><TH>Description</TH><TH>Default</TH></TR><TR><TD VAlign=top><tt>AdaptableBinaryFunction</tt></TD><TD VAlign=top>The type of the "outer" function in the function composition operation. That is, if the <tt>binary_compose</tt> is a function object <tt>h</tt> such that <tt>h(x) = f(g1(x), g2(x))</tt>, then <tt>AdaptableBinaryFunction</tt> is the type of <tt>f</tt>.</TD><TD VAlign=top> </TD></TR><TR><TD VAlign=top><tt>AdaptableUnaryFunction1</tt></TD><TD VAlign=top>The type of the first "inner" function in the function composition operation. That is, if the <tt>binary_compose</tt> is a function object <tt>h</tt> such that <tt>h(x) = f(g1(x), g2(x))</tt>, then <tt>AdaptableBinaryFunction</tt> is the type of <tt>g1</tt>.</TD><TD VAlign=top> </TD></TR><TR><TD VAlign=top><tt>AdaptableUnaryFunction2</tt></TD><TD VAlign=top>The type of the second "inner" function in the function composition operation. That is, if the <tt>binary_compose</tt> is a function object <tt>h</tt> such that <tt>h(x) = f(g1(x), g2(x))</tt>, then <tt>AdaptableBinaryFunction</tt> is the type of <tt>g2</tt>.</TD><TD VAlign=top> </TD></tr></table><h3>Model of</h3><A href="AdaptableUnaryFunction.html">Adaptable Unary Function</A><h3>Type requirements</h3><tt>AdaptableBinaryFunction</tt> must be a model of <A href="AdaptableBinaryFunction.html">Adaptable Binary Function</A>.<tt>AdaptableUnaryFunction1</tt> and <tt>AdaptableUnaryFunction2</tt> must bothbe models of <A href="AdaptableUnaryFunction.html">Adaptable Unary Function</A>. The argument types of <tt>AdaptableUnaryFunction1</tt> and <tt>AdaptableUnaryFunction2</tt> must be convertible to each other.The result types of <tt>AdaptableUnaryFunction1</tt> and<tt>AdaptableUnaryFunction2</tt> must be convertible, respectively, tothe first and second argument types of <tt>AdaptableBinaryFunction</tt>.<h3>Public base classes</h3><pre><A href="unary_function.html">unary_function</A><AdaptableUnaryFunction1::argument_type, AdaptableBinaryFunction::result_type></pre><h3>Members</h3><Table border><TR><TH>Member</TH><TH>Where defined</TH><TH>Description</TH></TR><TR><TD VAlign=top><tt>argument_type</tt></TD><TD VAlign=top> <A href="AdaptableUnaryFunction.html">Adaptable Unary Function</A></TD><TD VAlign=top>The type of the function object's argument:<tt>AdaptableUnaryFunction::argument_type</tt>.</TD></TR><TR><TD VAlign=top><tt>result_type</tt></TD><TD VAlign=top> <A href="AdaptableUnaryFunction.html">Adaptable Unary Function</A></TD><TD VAlign=top>The type of the result: <tt>AdaptableBinaryFunction::result_type</tt></TD></TR><TR><TD VAlign=top><pre>binary_compose(const AdaptableBinaryFunction& f, const AdaptableUnaryFunction1& g1, const AdaptableUnaryFunction1& g2); </pre></TD><TD VAlign=top><tt>binary_compose</tt></TD><TD VAlign=top>See below.</TD></TR><TR><TD VAlign=top><pre>template <class <A href="AdaptableBinaryFunction.html">AdaptableBinaryFunction</A>, class <A href="AdaptableUnaryFunction.html">AdaptableUnaryFunction</A>1, class <A href="AdaptableUnaryFunction.html">AdaptableUnaryFunction</A>2>binary_compose<AdaptableBinaryFunction, AdaptableUnaryFunction1, AdaptableUnaryFunction2>compose2(const AdaptableBinaryFunction&, const AdaptableUnaryFunction1&, const AdaptableUnaryFunction2&);</pre></TD><TD VAlign=top><tt>binary_compose</tt></TD><TD VAlign=top>See below.</TD></tr></table><h3>New members</h3>These members are not defined in the <A href="AdaptableUnaryFunction.html">Adaptable Unary Function</A>requirements, but are specific to <tt>binary_compose</tt>.<Table border><TR><TH>Member</TH><TH>Description</TH></TR><TR><TD VAlign=top><pre>binary_compose(const AdaptableBinaryFunction& f, const AdaptableUnaryFunction1& g1, const AdaptableUnaryFunction1& g2); </pre></TD><TD VAlign=top>The constructor. Constructs a <tt>binary_compose</tt> object such thatcalling that object with the argument <tt>x</tt> returns <tt>f(g1(x), g2(x))</tt>.</TD></TR><TR><TD VAlign=top><pre>template <class <A href="AdaptableBinaryFunction.html">AdaptableBinaryFunction</A>, class <A href="AdaptableUnaryFunction.html">AdaptableUnaryFunction</A>1, class <A href="AdaptableUnaryFunction.html">AdaptableUnaryFunction</A>2>binary_compose<AdaptableBinaryFunction, AdaptableUnaryFunction1, AdaptableUnaryFunction2>compose2(const AdaptableBinaryFunction&, const AdaptableUnaryFunction1&, const AdaptableUnaryFunction2&);</pre></TD><TD VAlign=top>Creates a <tt>binary_compose</tt> object. If <tt>f</tt>, <tt>g</tt>, and <tt>g2</tt> are, respectively,of classes <tt>AdaptableBinaryFunction</tt>, <tt>AdaptableUnaryFunction1</tt>, and<tt>AdaptableUnaryFunction2</tt>, then <tt>compose2(f, g1, g2)</tt> is equivalent to<tt>binary_compose<AdaptableBinaryFunction, AdaptableUnaryFunction1, AdaptableUnaryFunction2>(f, g1, g2)</tt>, but is more convenient.This is a global function, not a member function.</TD></tr></table><h3>Notes</h3><P><A name="1">[1]</A>This is a form of function composition. The <tt><A href="unary_compose.html">unary_compose</A></tt>adaptor allows composition of <A href="AdaptableUnaryFunction.html">Adaptable Unary Functions</A>; note,however, that once binary functions are introduced, there are severalpossible patterns of function composition. The <tt>binary_compose</tt>allows you to form a unary function by putting together two unaryfunctions and a binary function, but you could also, for example,imagine putting together two unary functions and a binary function toform a binary function. In that case, <tt>f</tt>, <tt>g1</tt>, and <tt>g2</tt> would becombined into a function object <tt>h</tt> such that <tt>h(x,y) = f(g1(x),g2(y))</tt>.<h3>See also</h3>The <A href="functors.html">function object overview</A>, <tt><A href="unary_compose.html">unary_compose</A></tt>, <tt><A href="binder1st.html">binder1st</A></tt>, <tt><A href="binder2nd.html">binder2nd</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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