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

 

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basic_string

basic_string_view (C++17)

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std::basic_string_view

Member functions basic_string_view::basic_string_view    basic_string_view::operator= Iterators basic_string_view::beginbasic_string_view::cbegin basic_string_view::endbasic_string_view::cend basic_string_view::rbeginbasic_string_view::crbegin basic_string_view::rendbasic_string_view::crend Element access basic_string_view::at basic_string_view::operator[] basic_string_view::front basic_string_view::back basic_string_view::data Capacity basic_string_view::sizebasic_string_view::length basic_string_view::max_size basic_string_view::empty Modifiers basic_string_view::remove_prefix basic_string_view::remove_suffix basic_string_view::swap

Operations basic_string_view::copy basic_string_view::substr basic_string_view::compare basic_string_view::starts_with (C++20) basic_string_view::ends_with (C++20) basic_string_view::contains (C++23) basic_string_view::find basic_string_view::rfind basic_string_view::find_first_of basic_string_view::find_last_of basic_string_view::find_first_not_of basic_string_view::find_last_not_of Constants basic_string_view::npos Non-member functions operator==operator!=operator<operator>operator<=operator>=operator<=> (until C++20)(until C++20)(until C++20)(until C++20)(until C++20)(C++20) operator<< operator""sv Helper classes hash<std::string_view>hash<std::wstring_view>hash<std::u8string_view>hash<std::u16string_view>hash<std::u32string_view> (C++20) Deduction guides(C++20)

 

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).

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

Return value

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

Complexity

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

Example

Run this code

#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'))
    );
}

See also

find (C++17)	find characters in the view (public member function)
find_first_of (C++17)	find first occurrence of characters (public member function)
find_last_of (C++17)	find last occurrence of characters (public member function)
find_first_not_of (C++17)	find first absence of characters (public member function)
find_last_not_of (C++17)	find last absence of characters (public member function)
rfind	find the last occurrence of a substring (public member function of std::basic_string<CharT,Traits,Allocator>)