Boolean literals
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[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] Keywords
[edit] 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
[edit] 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]
[edit] See also
C documentation for Predefined Boolean constants