Boolean literals

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[edit]Syntax


`true`	(1)

`false`	(2)

[edit]Explanation

The Boolean literals are the keywordstrue andfalse. They areprvalues of typebool.

[edit]Notes

SeeIntegral conversions for implicit conversions frombool to other types andboolean conversions for the implicit conversions from other types tobool.

[edit]Keywords

false,true

[edit]Example

Run this code

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

Output:

truefalse10

[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 forPredefined Boolean constants

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Boolean literals

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