std::boolalpha, std::noboolalpha
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boolalphanoboolalpha
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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 .
Contents
[edit] Parameters
str
-
reference to I/O stream
[edit] Return value
str (reference to the stream after manipulation).
[edit] Example
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
[edit] See also
[virtual]
(virtual protected member function of
std::numpunct<CharT>
) [edit]