.\" ident @(#)negate.3
.\" Standard Template Library
.\" $$RW_INSERT_HEADER "slyrs.man"
.TH negate 3C++ "02 Apr 1998" "Rogue Wave Software" "-"
.ce2
Standard C++ Library   
Copyright 1998, Rogue Wave Software, Inc.   

.SH NAME

\f2negate\fP

\ - Unary function object that returns the negation of its argument.



.SH  SYNOPSIS


.br
#include <functional>
.br
template <class T>
.br
struct negate : public unary_function<T, T>;



.SH  DESCRIPTION


negate is a unary function object. Its \f2operator()\fP returns the negation of its argument: \f2true\fP if its argument is \f2false\fP, or \f2false\fP if its argument is \f2true\fP. You can pass a negate object to any algorithm that requires a unary function. For example, the transform algorithm applies a unary operation to the values in a collection and stores the result.   negate could be used in that algorithm in the following manner:


.br
vector<int> vec1;
.br
vector<int> vecResult;
.br
.
.br
.
.br
.
.br
transform(vec1.begin(), vec1.end(), vecResult.begin(),
.RE
.RS 10
negate<int>());
.RE

After this call to transform, \f2vecResult(n)\fP contains the negation of the element in \f2vec1(n)\fP.



.SH  INTERFACE


.RE
.RS 0
template <class T>
.br
struct negate : unary_function<T, T> {
.RE
.RS 1
T operator() (const T&) const;
.RE
.RS 0
};



.SH  WARNINGS


If your compiler does not support default template parameters, then you always need to supply the \f2Allocator\fP template argument. For instance, you need to write:

\f2vector<int, allocator<int> >\fP

instead of: 

\f2vector<int>\fP

If your compiler does not support namespaces, then you do not need the using declaration for \f2std\fP.



.SH  SEE ALSO


Function_Objects, unary_function