function
<ios> <iostream>

std::noboolalpha

ios_base& noboolalpha (ios_base& str);
No alphanumerical bool values
Clears the boolalpha format flag for the str stream.

When the boolalpha format flag is not set, bool values are insterted/extracted as integral values (0 and 1) instead of their textual representations: true and false.

This flag can be set with the boolalpha manipulator.

For standard streams, the boolalpha flag is not set on initialization.

Parameters

str
Stream object whose format flag is affected.
Because this function is a manipulator, it is designed to be used alone with no arguments in conjunction with the insertion (<<) and extraction (>>) operations on streams (see example below).

Return Value

Argument str.

Example

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// modify boolalpha flag
#include <iostream>     // std::cout, std::boolalpha, std::noboolalpha

int main () {
  bool b = true;
  std::cout << std::boolalpha << b << '\n';
  std::cout << std::noboolalpha << b << '\n';
  return 0;
}

Output:
true
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Data races

Modifies str. Concurrent access to the same stream object may cause data races.

Exception safety

Basic guarantee: if an exception is thrown, str is in a valid state.

See also