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Boolean literals

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Contents

[edit] Syntax

true (1)
false (2)

[edit] Explanation

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

[edit] Notes

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

[edit] Example

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

Output:

true
false
1
0

[edit] References

  • C++23 standard (ISO/IEC 14882:2023):
  • 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]

[edit] See also

C documentation for Predefined Boolean constants