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hash_multimap::empty (STL/CLR)

Tests whether no elements are present.

    bool empty();

Remarks

The member function returns true for an empty controlled sequence. It is equivalent to hash_multimap::size (STL/CLR)() == 0. You use it to test whether the hash_multimap is empty.

Example

// cliext_hash_multimap_empty.cpp 
// compile with: /clr 
#include <cliext/hash_map> 
 
typedef cliext::hash_multimap<wchar_t, int> Myhash_multimap; 
int main() 
    { 
    Myhash_multimap c1; 
    c1.insert(Myhash_multimap::make_value(L'a', 1)); 
    c1.insert(Myhash_multimap::make_value(L'b', 2)); 
    c1.insert(Myhash_multimap::make_value(L'c', 3)); 
 
// display contents " [a 1] [b 2] [c 3]" 
    for each (Myhash_multimap::value_type elem in c1) 
        System::Console::Write(" [{0} {1}]", elem->first, elem->second); 
    System::Console::WriteLine(); 
    System::Console::WriteLine("size() = {0}", c1.size()); 
    System::Console::WriteLine("empty() = {0}", c1.empty()); 
 
// clear the container and reinspect 
    c1.clear(); 
    System::Console::WriteLine("size() = {0}", c1.size()); 
    System::Console::WriteLine("empty() = {0}", c1.empty()); 
    return (0); 
    } 
 
 [a 1] [b 2] [c 3]
size() = 3
empty() = False
size() = 0
empty() = True

Requirements

Header: <cliext/hash_map>

Namespace: cliext

See Also

Concepts

hash_multimap (STL/CLR)

hash_multimap::size (STL/CLR)