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std::basic_string_view<CharT,Traits>::rfind

From cppreference.com
 
 
 
 
constexpr size_type rfind( basic_string_view v, size_type pos = npos ) const noexcept;
(1) (since C++17)
constexpr size_type rfind( CharT ch, size_type pos = npos ) const noexcept;
(2) (since C++17)
constexpr size_type rfind( const CharT* s, size_type pos, size_type count ) const;
(3) (since C++17)
constexpr size_type rfind( const CharT* s, size_type pos = npos ) const;
(4) (since C++17)

Finds the last substring equal to the given character sequence. Search begins at pos, i.e. the found substring must not begin in a position following pos. If npos or any value not smaller than size()-1 is passed as pos, whole string will be searched.

1) Finds the last occurrence of v in this view, starting at position pos.
2) Equivalent to rfind(basic_string_view(std::addressof(ch), 1), pos).
3) Equivalent to rfind(basic_string_view(s, count), pos).
4) Equivalent to rfind(basic_string_view(s), pos).

Contents

[edit] Parameters

v - view to search for
pos - position at which to start the search
count - length of substring to search for
s - pointer to a character string to search for
ch - character to search for

[edit] Return value

Position of the first character of the found substring or npos if no such substring is found.

[edit] Complexity

O(size() * v.size()) at worst.

[edit] Example

#include <string_view>
 
int main()
{
    using namespace std::literals;
    constexpr auto N = std::string_view::npos;
 
    static_assert(true
        && (6 == "AB AB AB"sv.rfind("AB"))
        && (6 == "AB AB AB"sv.rfind("ABCD", N, 2))
        && (3 == "AB AB AB"sv.rfind("AB", 5))
        && (2 == "B AB AB "sv.rfind("AB", 2))
        && (N == "B AB AB "sv.rfind("AB", 1))
        && (5 == "B AB AB "sv.rfind('A'))
        && (4 == "AB AB AB"sv.rfind('B', 4))
        && (N == "AB AB AB"sv.rfind('C'))
    );
}

[edit] See also

(C++17)
find characters in the view
(public member function) [edit]
find first occurrence of characters
(public member function) [edit]
find last occurrence of characters
(public member function) [edit]
find first absence of characters
(public member function) [edit]
find last absence of characters
(public member function) [edit]
find the last occurrence of a substring
(public member function of std::basic_string<CharT,Traits,Allocator>) [edit]