class template
<functional>
std::logical_and
template <class T> struct logical_and;
Logical AND function object class
Binary function object class whose call returns the result of the logical "and" operation between its two arguments (as returned by operator &&).
Generically, function objects are instances of a class with member function operator() defined. This member function allows the object to be used with the same syntax as a function call.
It is defined with the same behavior as:
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template <class T> struct logical_and : binary_function <T,T,bool> {
bool operator() (const T& x, const T& y) const {return x&&y;}
};
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template <class T> struct logical_and {
bool operator() (const T& x, const T& y) const {return x&&y;}
typedef T first_argument_type;
typedef T second_argument_type;
typedef bool result_type;
};
Template parameters
- T
- Type of the arguments passed to the functional call.
The type shall support the operation (operator&&).
Member types
| member type | definition | notes |
|---|
| first_argument_type | T | Type of the first argument in member operator() |
| second_argument_type | T | Type of the second argument in member operator() |
| result_type | bool | Type returned by member operator() |
Member functions
- bool operator() (const T& x, const T& y)
- Member function returning whether both its arguments are considered true (
x&&y).
Example
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// logical_and example
#include <iostream> // std::cout, std::boolalpha
#include <functional> // std::logical_and
#include <algorithm> // std::transform
int main () {
bool foo[] = {true,false,true,false};
bool bar[] = {true,true,false,false};
bool result[4];
std::transform (foo, foo+4, bar, result, std::logical_and<bool>());
std::cout << std::boolalpha << "Logical AND:\n";
for (int i=0; i<4; i++)
std::cout << foo[i] << " AND " << bar[i] << " = " << result[i] << "\n";
return 0;
}
Output:
Logical AND:
true AND true = true
false AND true = false
true AND false = false
false AND false = false
See also
- logical_or
- Logical OR function object class (class template)
- logical_not
- Logical NOT function object class (class template)