[string.view.template.general] (original) (raw)
27 Strings library [strings]
27.3 String view classes [string.view]
27.3.3 Class template basic_string_view [string.view.template]
27.3.3.1 General [string.view.template.general]
namespace std { template<class charT, class traits = char_traits<charT>> class basic_string_view { public: using traits_type = traits;using value_type = charT;using pointer = value_type*;using const_pointer = const value_type*;using reference = value_type&;using const_reference = const value_type&;using const_iterator = implementation-defined; using iterator = const_iterator;203 using const_reverse_iterator = reverse_iterator<const_iterator>;using reverse_iterator = const_reverse_iterator;using size_type = size_t;using difference_type = ptrdiff_t;static constexpr size_type npos = size_type(-1);constexpr basic_string_view() noexcept;constexpr basic_string_view(const basic_string_view&) noexcept = default;constexpr basic_string_view& operator=(const basic_string_view&) noexcept = default;constexpr basic_string_view(const charT* str); basic_string_view(nullptr_t) = delete;constexpr basic_string_view(const charT* str, size_type len);template<class It, class End> constexpr basic_string_view(It begin, End end);template<class R> constexpr explicit basic_string_view(R&& r);constexpr const_iterator begin() const noexcept;constexpr const_iterator end() const noexcept;constexpr const_iterator cbegin() const noexcept;constexpr const_iterator cend() const noexcept;constexpr const_reverse_iterator rbegin() const noexcept;constexpr const_reverse_iterator rend() const noexcept;constexpr const_reverse_iterator crbegin() const noexcept;constexpr const_reverse_iterator crend() const noexcept;constexpr size_type size() const noexcept;constexpr size_type length() const noexcept;constexpr size_type max_size() const noexcept;constexpr bool empty() const noexcept;constexpr const_reference operator[](size_type pos) const;constexpr const_reference at(size_type pos) const; constexpr const_reference front() const;constexpr const_reference back() const;constexpr const charT* data() const noexcept;constexpr void remove_prefix(size_type n);constexpr void remove_suffix(size_type n);constexpr void swap(basic_string_view& s) noexcept;constexpr size_type copy(charT* s, size_type n, size_type pos = 0) const; constexpr basic_string_view substr(size_type pos = 0, size_type n = npos) const; constexpr basic_string_view subview(size_type pos = 0, size_type n = npos) const; constexpr int compare(basic_string_view s) const noexcept;constexpr int compare(size_type pos1, size_type n1, basic_string_view s) const; constexpr int compare(size_type pos1, size_type n1, basic_string_view s, size_type pos2, size_type n2) const; constexpr int compare(const charT* s) const;constexpr int compare(size_type pos1, size_type n1,const charT* s) const; constexpr int compare(size_type pos1, size_type n1, const charT* s, size_type n2) const; constexpr bool starts_with(basic_string_view x) const noexcept;constexpr bool starts_with(charT x) const noexcept;constexpr bool starts_with(const charT* x) const;constexpr bool ends_with(basic_string_view x) const noexcept;constexpr bool ends_with(charT x) const noexcept;constexpr bool ends_with(const charT* x) const;constexpr bool contains(basic_string_view x) const noexcept;constexpr bool contains(charT x) const noexcept;constexpr bool contains(const charT* x) const;constexpr size_type find(basic_string_view s, size_type pos = 0) const noexcept;constexpr size_type find(charT c, size_type pos = 0) const noexcept;constexpr size_type find(const charT* s, size_type pos, size_type n) const;constexpr size_type find(const charT* s, size_type pos = 0) const;constexpr size_type rfind(basic_string_view s, size_type pos = npos) const noexcept;constexpr size_type rfind(charT c, size_type pos = npos) const noexcept;constexpr size_type rfind(const charT* s, size_type pos, size_type n) const;constexpr size_type rfind(const charT* s, size_type pos = npos) const;constexpr size_type find_first_of(basic_string_view s, size_type pos = 0) const noexcept;constexpr size_type find_first_of(charT c, size_type pos = 0) const noexcept;constexpr size_type find_first_of(const charT* s, size_type pos, size_type n) const;constexpr size_type find_first_of(const charT* s, size_type pos = 0) const;constexpr size_type find_last_of(basic_string_view s, size_type pos = npos) const noexcept;constexpr size_type find_last_of(charT c, size_type pos = npos) const noexcept;constexpr size_type find_last_of(const charT* s, size_type pos, size_type n) const;constexpr size_type find_last_of(const charT* s, size_type pos = npos) const;constexpr size_type find_first_not_of(basic_string_view s, size_type pos = 0) const noexcept;constexpr size_type find_first_not_of(charT c, size_type pos = 0) const noexcept;constexpr size_type find_first_not_of(const charT* s, size_type pos, size_type n) const;constexpr size_type find_first_not_of(const charT* s, size_type pos = 0) const;constexpr size_type find_last_not_of(basic_string_view s, size_type pos = npos) const noexcept;constexpr size_type find_last_not_of(charT c, size_type pos = npos) const noexcept;constexpr size_type find_last_not_of(const charT* s, size_type pos, size_type n) const;constexpr size_type find_last_not_of(const charT* s, size_type pos = npos) const;private: const charT* data_; size_type size_; };template<class It, class End> basic_string_view(It, End) -> basic_string_view<iter_value_t<It>>;template<class R> basic_string_view(R&&) -> basic_string_view<ranges::range_value_t<R>>;}
In every specialization basic_string_view<charT, traits>, the type traits shall meet the character traits requirements ([char.traits]).
[Note 1:
The program is ill-formed if traits::char_type is not the same type as charT.
— _end note_]
For a basic_string_view str, any operation that invalidates a pointer in the range[str.data(), str.data() + str.size()) invalidates pointers, iterators, and references to elements of str.
The complexity of basic_string_view member functions is unless otherwise specified.