ios manipulators boolalpha() function in C++

The boolalpha() method of stream manipulators in C++ is used to set the boolalpha format flag for the specified str stream.

Syntax:

ios_base& boolalpha (ios_base& str)

Parameters: This method accepts str as a a parameter which is the stream for which the format flag is affected.

Return Value: This method returns the stream str with boolalpha format flag set.

Example 1:

// C++ code to demonstrate
// the working of boolalpha() function

#include <iostream>

using namespace std;

int main()
{

    // Initializing the boolean flag
    bool flag = true;

    // Using boolalpha()
    cout << "boolalpha flag: "
         << boolalpha << flag << endl;

    return 0;
}

Output:

boolalpha flag: true

Example 2:

// C++ code to demonstrate
// the working of boolalpha() function

#include <iostream>

using namespace std;

int main()
{

    // Initializing the boolean flag
    bool flag = false;

    // Using boolalpha()
    cout << "boolalpha flag: "
         << boolalpha << flag << endl;

    return 0;
}

Output:

boolalpha flag: false

Reference: http://www.cplusplus.com/reference/ios/boolalpha/