Section 3: library functions
std::weibull_distribution – std::weibull_distribution Synopsis Defined in header <random> template< class RealType = double > (since C++11) class weibull_distribution; The weibull_distribution meets the requirements of a RandomNumberDistribution and produces random numbers according to the Weibull_distribution: f(x;a,b) = a b ⎛ ⎜ ⎝ x b ⎞ ⎟ ⎠a-1 exp⎛ ⎜ ⎝-⎛ ⎜ ⎝ x b ⎞ ⎟…
std::weak_ptr<T>::~weak_ptr – std::weak_ptr<T>::~weak_ptr Synopsis ~weak_ptr(); (since C++11) Destroys the weak_ptr object. Results in no effect to the managed object.
std::weak_ptr<T>::use_count – std::weak_ptr<T>::use_count Synopsis long use_count() const noexcept; (since C++ 11) Returns the number of shared_ptr instances that share ownership of the managed object, or 0 if the managed object has already been deleted, i.e. *this is empty. Parameters (none) Return value The number of shared_ptr instances sharing the ownership of the managed object at…
std::weak_ptr<T>::swap – std::weak_ptr<T>::swap Synopsis void swap(weak_ptr &r) noexcept; (since C++ 11) Exchanges the contents of *this and r Parameters r – smart pointer to exchange the contents with Return value (none)
std::weak_ptr<T>::reset – std::weak_ptr<T>::reset Synopsis void reset() noexcept; (since C++ 11) Releases the reference to the managed object. After the call *this manages no object. Parameters (none) Return value (none)
std::weak_ptr<T>::owner_before – std::weak_ptr<T>::owner_before Synopsis template <class Y> (until C++ 17) bool owner_before(const weak_ptr<Y> &other) const; template <class Y> (since C++ 17) bool owner_before(const weak_ptr<Y> &other) const noexcept; template <class Y> (until C++ 17) bool owner_before(const std::shared_ptr<Y> &other) const; template <class Y> (since C++ 17) bool owner_before(const std::shared_ptr<Y> &other) const noexcept; Checks whether this weak_ptr precedes…
std::weak_ptr<T>::operator= – std::weak_ptr<T>::operator= Synopsis weak_ptr &operator=(const weak_ptr &r) noexcept; (1)(since C++ 11) template <class Y> (2)(since C++ 11) weak_ptr & operator=(const weak_ptr<Y> &r) noexcept; template <class Y> (3)(since C++ 11) weak_ptr & operator=(const shared_ptr<Y> &r) noexcept; weak_ptr &operator=(weak_ptr &&r) noexcept; (4)(since C++ 14) template <class Y> (5)(since C++ 14) weak_ptr & operator=(weak_ptr<Y> &&r) noexcept; Replaces…
std::weak_ptr<T>::lock – std::weak_ptr<T>::lock Synopsis std::shared_ptr<T> lock() const noexcept; (since C++11) Creates a new std::shared_ptr that shares ownership of the managed object. If there is no managed object, i.e. *this is empty, then the returned shared_ptr also is empty. Effectively returns expired() ? shared_ptr<T>() : shared_ptr<T>(*this), executed atomically. Parameters (none) Return value A shared_ptr which shares…
std::weak_ptr<T>::expired – std::weak_ptr<T>::expired Synopsis bool expired() const noexcept; (since C++11) Equivalent to use_count() == 0. The destructor for the managed object may not yet have been called, but this object’s destruction is imminent (or may have already happened). Parameters (none) Return value true if the managed object has already been deleted, false otherwise. Notes This…
std::weak_ptr – std::weak_ptr Synopsis Defined in header <memory> template< class T > class weak_ptr; (since C++11) std::weak_ptr is a smart pointer that holds a non-owning ("weak") reference to an object that is managed by std::shared_ptr. It must be converted to std::shared_ptr in order to access the referenced object. std::weak_ptr models temporary ownership: when an object…
std::weak_ordering – std::weak_ordering Synopsis Defined in header <compare> class weak_ordering; (since C++20) The class type std::weak_ordering is the result type of a three-way_comparison that * admits all six relational operators (==, !=, <, <=, >, >=) * does not imply substitutability: if a is equivalent to b, f(a) may not be equivalent to f(b), where…
std::weak_order – std::weak_order Synopsis Defined in header<compare> template <class T> (since C++ 20) constexpr std::weak_ordering weak_order(const T &a, const T &b); Compares two values using 3-way comparison and produces a result of type std::weak_ordering Specifically, * If the expression a <=> b is well-formed and its result is convertible to std::weak_ordering, returns that result. *…
std::weak_equality – std::weak_equality Synopsis Defined in header <compare> class weak_equality; (since C++20) The class type std::weak_equality is the result type of a three-way_comparison that * admits only equality and inequality comparisons (no less-than/greater-than) * does not imply substitutability: if a is equivalent to b, f(a) may not be equivalent to f(b), where f denotes a…
std::weak_equal – std::weak_equal Synopsis Defined in header<compare> template <class T> (since C++ 20) constexpr std::weak_equality weak_equal(const T &a, const T &b); Compares two values using 3-way comparison and produces a result of type std::weak_equality Specifically, * If the expression a <=> b is well-formed and its result is convertible to std::weak_equality, returns that result. *…
std::wctype – std::wctype Synopsis Defined in header<cwctype> std::wctype_t wctype(const char *str); Constructs a value of type std::wctype_t that describes a LC_CTYPE category of wide character classification. It may be one of the standard classification categories, or a locale-specific category, such as "jkanji". Parameters str – C string holding the name of the desired category The…
std::wctrans – std::wctrans Synopsis Defined in header<cwctype> std::wctrans_t wctrans(const char *str); Constructs a value of type std::wctrans_t that describes a LC_CTYPE category of wide character mapping. It may be one of the standard mappings, or a locale-specific mapping, such as "tojhira" or "tojkana". Parameters C string holding the name of the desired mapping. The following…
std::wctob – std::wctob Synopsis Defined in header<cwchar> int wctob(std::wint_t c); Narrows a wide character c if its multibyte character equivalent in the initial shift state is a single byte. This is typically possible for the characters from the ASCII character set, since most multibyte encodings (such as UTF-8) use single bytes to encode those characters….
std::wcsxfrm – std::wcsxfrm Synopsis Defined in header<cwchar> std::size_t strxfrm(wchar_t *dest, const wchar_t *src, std::size_t count); Transforms the null-terminated wide string pointed to by src into the implementation-defined form such that comparing two transformed strings with std::wcscmp gives the same result as comparing the original strings with std::wcscoll, in the current C locale. The first count…
std::wcstoul,std::wcstoull – std::wcstoul,std::wcstoull Synopsis Defined in header <cwchar> unsigned long wcstoul( const wchar_t* str, wchar_t** str_end, int base ); unsigned long long wcstoull( const wchar_t* str, wchar_t** str_end, int base ); (since C++11) Interprets an unsigned integer value in a wide string pointed to by str. Discards any whitespace characters (as identified by calling isspace())…
std::wcstol,std::wcstoll – std::wcstol,std::wcstoll Synopsis Defined in header <cwchar> long wcstol( const wchar_t* str, wchar_t** str_end, int base ); long long wcstoll( const wchar_t* str, wchar_t** str_end, int base ); (since C++11) Interprets an integer value in a wide string pointed to by str. Discards any whitespace characters (as identified by calling isspace()) until the first…