Boolean literals

 

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Syntax

true	(1)
false	(2)

Explanation

The Boolean literals are the keywords true and false. They are prvalues of type bool.

Notes

See Integral conversions for implicit conversions from bool to other types and boolean conversions for the implicit conversions from other types to bool.

Keywords

false, true

Example

Run this code

#include <iostream>
 
int main()
{
    std::cout << std::boolalpha
              << true << '\n'
              << false << '\n'
              << std::noboolalpha
              << true << '\n'
              << false << '\n';
}

Output:

true
false
1
0

References

• C++23 standard (ISO/IEC 14882:2024):

• 5.13.6 Boolean literals [lex.bool]

• C++20 standard (ISO/IEC 14882:2020):

• 5.13.6 Boolean literals [lex.bool]

• C++17 standard (ISO/IEC 14882:2017):

• 5.13.6 Boolean literals [lex.bool]

• C++14 standard (ISO/IEC 14882:2014):

• 2.13.6 Boolean literals [lex.bool]

• C++11 standard (ISO/IEC 14882:2011):

• 2.13.6 Boolean literals [lex.bool]

• C++98 standard (ISO/IEC 14882:1998):

• 2.13.5 Boolean literals [lex.bool]

See also

C documentation for Predefined Boolean constants