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 an

Defined in header <ios> enum class io_errc; (since C++11) The scoped enumeration std::io_errc defines the error codes reported by I/O streams in std::ios_base::failure exception objects. Only one error code (std::io_errc::stream) is required, although the implementation may define additional error codes. Because the appropriate specialization of std::is_error_code_enum is provided, values of type std::io_errc are implicitly convertible to std::error_code. Member constants

Defined in header <ios> std::error_code make_error_code( std::io_errc e ); (since C++11) Constructs an std::error_code object from a value of type std::io_errc as if by return std::error_code(static_cast<int>(e), std::iostream_category()). This function is called by the constructor of std::error_code when given an std::io_errc argument. Parameters e - error code number Return value A value of type std::error_code that holds the error code number from e a

Defined in header <ios> std::error_condition make_error_condition( std::io_errc e ); (since C++11) Constructs an std::error_condition object from a value of type std::io_errc as if by return std::error_condition(static_cast<int>(e), std::iostream_category()). Parameters e - error code number Return value A value of type std::error_condition that holds the error code number from e associated with the error category "iostream". Exceptions noexcept spec

Defined in header <iomanip> /*unspecified*/ setprecision( int n ); When used in an expression out << setprecision(n) or in >> setprecision(n), sets the precision parameter of the stream out or in to exactly n. Parameters n - new value for precision Return value Returns an object of unspecified type such that if str is the name of an output stream of type std::basic_ostream<CharT, Traits> or an input stream of type std::basic_istream<CharT,

Defined in header <ios> std::ios_base& showpos( std::ios_base& str ); (1) std::ios_base& noshowpos( std::ios_base& str ); (2) Enables or disables the display of the plus sign '+' in non-negative integer output. Has no effect on input. 1) enables the showpos flag in the stream str as if by calling str.setf(std::ios_base::showpos). 2) disables the showpos flag in the stream str as if by calling str.unsetf(std::ios_base::showpos). This is an I/O manipulat

Defined in header <cmath> float tan( float arg ); (1) double tan( double arg ); (2) long double tan( long double arg ); (3) double tan( Integral arg ); (4) (since C++11) Computes the tangent of arg (measured in radians). 4) A set of overloads or a function template accepting an argument of any integral type. Equivalent to 2) (the argument is cast to double). Parameters arg - value representing angle in radians, of a floating-point

template< class Function, class... Args > void swap( packaged_task<Function(Args...)> &lhs, packaged_task<Function(Args...)> &rhs ); (since C++11) Specializes the std::swap algorithm for std::packaged_task. Exchanges the state of lhs with that of rhs. Effectively calls lhs.swap(rhs). Parameters lhs, rhs - packaged tasks whose states to swap Return value (none). Exceptions noexcept specification: noexcept Example See also s

(1) explicit lock_guard( mutex_type& m ); (until C++17) explicit lock_guard( MutexTypes&... m ); (since C++17) (2) lock_guard( mutex_type& m, std::adopt_lock_t t ); (until C++17) lock_guard( MutexTypes&... m, std::adopt_lock_t t ); (since C++17) lock_guard( const lock_guard& ) = delete; (3) (since C++11) Acquires ownership of the given mutex m. 1) Effectively calls m.lock(). The behavior is undefined if m is not a recursive mutex and the cur

Defined in header <future> std::error_code make_error_code( std::future_errc e ); (since C++11) Constructs an std::error_code object from a value of type std::future_errc as if by: std::error_code(static_cast<int>(e), std::future_category()). This function is called by the constructor of std::error_code when given an std::future_errc argument. Parameters e - error code number Return value A value of type std::error_code that holds the error code number f