std::boolal...:noboolalpha(3)

✨ NAME ✨

Okay so this is the std::boolal...:noboolalpha(3) page from the C++ Standard Libary — yes bestie, that’s the manual name folded in near the top instead of copying the whole header line like a bot 💅. The name itself is:

std::boolalpha,std::noboolalpha - std::boolalpha,std::noboolalpha

Lowkey iconic that it just says the same thing twice, but we respect the source ✨.

🌸 Synopsis 🌸

Defined in header <ios>:

std::ios_base& boolalpha( std::ios_base& str );   (1)
std::ios_base& noboolalpha( std::ios_base& str ); (2)

1. Enables the boolalpha flag in the stream str as if by calling str.setf(std::ios_base::boolalpha).
2. Disables the boolalpha flag in the stream str as if by calling str.unsetf(std::ios_base::boolalpha).

std::boolalpha is an I/O manipulator, so it may be called with an expression such as

out << std::boolalpha

for any out of type std::basic_ostream, or with an expression such as

in >> std::boolalpha

for any in of type std::basic_istream.

🫶 Parameters 🫶

• str — reference to I/O stream

💖 Return value 💖

str (reference to the stream after manipulation).

🎀 Example 🎀

Here’s the code, bestie — run it, don’t just look at it 🙈:

// Run this code

#include <iostream>
#include <sstream>

int main()
{
    // boolalpha output
    std::cout << "default true: " << true << '\n'
              << "default false: " << false << '\n'
              << std::boolalpha
              << "boolalpha true: " << true << '\n'
              << "boolalpha false: " << false << '\n'
              << std::noboolalpha
              << "noboolalpha true: " << true << '\n'
              << "noboolalpha false: " << false << '\n';

    // boolalpha parse
    bool b1, b2;
    std::istringstream is("true false");
    is >> std::boolalpha >> b1 >> b2;

    std::cout << '"' << is.str() << "\" parsed as: "
              << std::boolalpha << b1 << ' ' << b2 << '\n';
}

🍓 Output: 🍓

default true: 1
default false: 0
boolalpha true: true
boolalpha false: false
noboolalpha true: 1
noboolalpha false: 0
"true false" parsed as: true false

👀 See also 👀

• resetiosflags — clears the specified ios_base flags (function)
• setiosflags — sets the specified ios_base flags (function)
• do_truename — provides the string to use as the name of the boolean true and false
• do_falsename — (virtual protected member function of std::numpunct<CharT>) [virtual]

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And that’s the whole page, bestie 💖. Source/version/date sign-off: http://cppreference.com, 2024.06.10, std::boolal...:noboolalpha(3). Periodt ✨