bool empty() const; Checks if the container has no elements, i.e. whether begin() == end(). Parameters (none). Return value true if the container is empty, false otherwise. Exceptions (none) (until C++11) noexcept specification: noexcept (since C++11) Complexity Constant. Example The following code uses empty to check if a std::list<int> contains any elements: #include <list> #include <iostream> int main() { std::list<int> numbers; s

For an unqualified name, that is a name that does not appear to the right of a scope resolution operator ::, name lookup examines the scopes as described below, until it finds at least one declaration of any kind, at which time the lookup stops and no further scopes are examined. (Note: lookup from some contexts skips some declarations, for example, lookup of the name used to the left of :: ignores function, variable, and enumerator declarations, lookup of a name used as a base class specifier

Usage alternative operators: as an alternative for |=

static std::time_t to_time_t( const time_point& t ); (since C++11) Converts t to a std::time_t type. If std::time_t has lower precision, it is implementation-defined whether the value is rounded or truncated. Parameters t - system clock time point to convert Return value A std::time_t value representing t. Exceptions noexcept specification: noexcept See also from_time_t [static] converts std::time_t to a system clock time point (public static member funct

std::basic_string<CharT, Traits, Allocator> str() const; (1) void str( const std::basic_string<CharT, Traits, Allocator>& s); (2) Gets and sets the underlying string. 1) Creates and returns a std::basic_string object containing a copy of this std::basic_stringbuf's underlying character sequence. For input-only streams, the returned string contains the characters from the range [eback(), egptr()). For input/output or output-only streams, contains the characters fro

static const int digits10; (until C++11) static constexpr int digits10 (since C++11) The value of std::numeric_limits<T>::digits10 is the number of base-10 digits that can be represented by the type T without change, that is, any number with this many decimal digits can be converted to a value of type T and back to decimal form, without change due to rounding or overflow. For base-radix types, it is the value of digits (digits-1 for floating-point types) multiplied by log10(

Usage typeid operator

Usage automatic storage duration specifier (deprecated). (until C++17) The keyword is unused and reserved. (since C++17)

The floating-point environment is the set of floating-point status flags and control modes supported by the implementation. It is thread-local, each thread inherits the initial state of its floating-point environment from the parent thread. Floating-point operations modify the floating-point status flags to indicate abnormal results or auxiliary information. The state of floating-point control modes affects the outcomes of some floating-point operations. The floating-point environment access an

Defined in header <complex> template< class T > T arg( const complex<T>& z ); (1) long double arg( long double z ); (2) (since C++11) template< class DoubleOrIngeter > double arg( DoubleOrInteger z ); (3) (since C++11) float arg( float z ); (4) (since C++11) Calculates the phase angle (in radians) of the complex number z. (since C++11)Additional overloads are provided for float, double, long double, and all integer types, which are t