Note
Access to this page requires authorization. You can try signing in or changing directories.
Access to this page requires authorization. You can try changing directories.
Note
This API is obsolete. The alternative is unordered_multimap Class.
Retrieves a copy of the comparison object used to order keys in a hash_multimap.
key_compare key_comp( ) const;
Return Value
Returns the function object that a hash_multimap uses to order its elements.
Remarks
The stored object defines the member function
bool operator(const Key& _Left**, const Key&** _Right**);**
which returns true if _Left precedes and is not equal to _Right in the sort order.
In Visual C++ .NET 2003, members of the <hash_map> and <hash_set> header files are no longer in the std namespace, but rather have been moved into the stdext namespace. See The stdext Namespace for more information.
Example
// hash_multimap_key_comp.cpp
// compile with: /EHsc
#include <hash_map>
#include <iostream>
int main( )
{
using namespace std;
using namespace stdext;
hash_multimap <int, int, hash_compare<int, less<int> > > hm1;
hash_multimap <int, int, hash_compare<int, less<int> >
>::key_compare kc1 = hm1.key_comp( ) ;
bool result1 = kc1( 2, 3 ) ;
if( result1 == true )
{
cout << "kc1( 2,3 ) returns value of true,\n"
<< "where kc1 is the function object of hm1.\n"
<< endl;
}
else
{
cout << "kc1( 2,3 ) returns value of false,\n"
<< "where kc1 is the function object of hm1.\n"
<< endl;
}
hash_multimap <int, int, hash_compare<int, greater<int> > > hm2;
hash_multimap <int, int, hash_compare<int, greater<int> >
>::key_compare kc2 = hm2.key_comp( );
bool result2 = kc2( 2, 3 ) ;
if( result2 == true )
{
cout << "kc2( 2,3 ) returns value of true,\n"
<< "where kc2 is the function object of hm2."
<< endl;
}
else
{
cout << "kc2( 2,3 ) returns value of false,\n"
<< "where kc2 is the function object of hm2."
<< endl;
}
}
Output
kc1( 2,3 ) returns value of true,
where kc1 is the function object of hm1.
kc2( 2,3 ) returns value of false,
where kc2 is the function object of hm2.
Requirements
Header: <hash_map>
Namespace: stdext