map::empty (STL/CLR)
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Tests whether no elements are present.
Syntax
bool empty();
Remarks
The member function returns true for an empty controlled sequence. It is equivalent to map::size (STL/CLR)() == 0
. You use it to test whether the map is empty.
Example
// cliext_map_empty.cpp
// compile with: /clr
#include <cliext/map>
typedef cliext::map<wchar_t, int> Mymap;
int main()
{
Mymap c1;
c1.insert(Mymap::make_value(L'a', 1));
c1.insert(Mymap::make_value(L'b', 2));
c1.insert(Mymap::make_value(L'c', 3));
// display contents " [a 1] [b 2] [c 3]"
for each (Mymap::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/map>
Namespace: cliext