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

.SH NAME

\f2pair\fP

\ - A template for heterogeneous pairs of values.



.SH  SYNOPSIS


.br
#include <utility>
.br
template <class T1, class T2>
.br
struct pair ;



.SH  DESCRIPTION


The pair class is a template for encapsulating pairs of values that may be of different types.



.SH  INTERFACE


.br
template <class T1, class T2>
.br
struct pair {
.RE
.RS 7
typedef T1 first_type;
.br
typedef T2 second_type;
.br
T1 first;
.br
T2 second;
.br
pair();
.br
pair (const T1&, const T2&);
.br
template <class V, class U>
.br
pair (const pair <V, U>& p);
.RE
.RS 8
~pair();
.RE
.RS 0
};
.br

.br
template <class T1, class T2>
.br
bool operator== (const pair<T1, T2>&,
.RE
.RS 17
const pair T1, T2>&);
.RE
.RS 0

.br
template <class T1, class T2>
.br
bool operator!= (const pair<T1, T2>&,
.RE
.RS 17
const pair T1, T2>&);
.RE
.RS 0

.br
template <class T1, class T2>
.br
bool operator< (const pair<T1, T2>&,
.RE
.RS 16
const pair T1, T2>&);
.RE
.RS 0

.br
template <class T1, class T2>
.br
bool operator> (const pair<T1, T2>&,
.RE
.RS 16
const pair T1, T2>&);
.RE
.RS 0

.br
template <class T1, class T2>
.br
bool operator<= (const pair<T1, T2>&,
.RE
.RS 16
const pair T1, T2>&);
.RE
.RS 0

.br
template <class T1, class T2>
.br
bool operator>= (const pair<T1, T2>&,
.RE
.RS 16
const pair T1, T2>&);
.RE
.RS 0

.br
template <class T1, class T2>
.br
pair<T1,T2> make_pair (const T1&, const T2&);



.SH  TYPES



.br
first_type
.RE
.RS 3


Type of the first element in a pair.

.RE


.br
second_type
.RE
.RS 3


Type of the second element in a pair.

.RE



.SH  CONSTRUCTORS 



.br
pair ();
.RE
.RS 3


Default constructor. Initializes \f2first\fP and \f2second\fP using their default constructors.

.RE


.br
pair (const T1& x, const T2& y);
.RE
.RS 3


Creates a pair of types \f2T1\fP and \f2T2\fP, making the necessary conversions in\f2 x\fP and \f2y\fP.

.RE


.br
template <class V, class U>
.br
pair (const pair <V, U>& p);
.RE
.RS 3


Copies \f2first\fP and \f2second\fP from the corresponding elements of \f2p\fP.

.RE



.SH  DESTRUCTORS



.br
~pair ();


.SH  NON-MEMBER OPERATORS



.br
template <class T1, class T2>
.br
bool operator== (const pair<T1, T2>& x,
.RE
.RS 17
const pair T1, T2>& y);
.RE
.RS 3


Returns \f2true\fP if \f2(x.first == y.first && x.second == y.second\fP) is \f2true\fP. Otherwise it returns \f2false\fP.

.RE


.RE
.RS 0
template <class T1, class T2>
.br
bool operator!= (const pair<T1, T2>& x,
.RE
.RS 17
const pair T1, T2>& y);
.RE
.RS 3


Returns \f2!(x==y)\fP.

.RE


.RE
.RS 0
template <class T1, class T2>
.br
bool operator< (const pair<T1, T2>& x,
.RE
.RS 15
const pair T1, T2>& y);
.RE
.RS 3


Returns \f2true\fP if \f2(x.first < y.first || (!(y.first < x.first) && x.second < y.second))\fP is \f2true\fP. Otherwise it returns \f2false\fP.

.RE


.RE
.RS 0
template <class T1, class T2>
.br
bool operator> (const pair<T1, T2>& x,
.RE
.RS 15
const pair T1, T2>& y);
.RE
.RS 3


Returns \f2y < x\fP.

.RE


.RE
.RS 0
template <class T1, class T2>
.br
bool operator<= (const pair<T1, T2>& x,
.RE
.RS 15
const pair T1, T2>& y);
.RE
.RS 3


Returns \f2!(y < x)\fP.

.RE


.RE
.RS 0
template <class T1, class T2>
.br
bool operator>= (const pair<T1, T2>& x,
.RE
.RS 15
const pair T1, T2>& y);
.RE
.RS 3


Returns \f2!(x < y)\fP.

.RE



.SH  NON-MEMBER FUNCTIONS



.RE
.RS 0
template <class T1, class T2>
.br
pair<T1,T2>
.br
make_pair(x,y);
.RE
.RS 3


\f2make_pair(x,y)\fP creates a pair by deducing and returning the types of \f2x\fP and \f2y\fP.

.RE