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

Since C++17

Finds the last substring that is equal to the given character sequence. The search begins at pos and proceeds from right to left (thus, the found substring, if any, cannot begin in a position following pos). If npos or any value not smaller than size()- 1 is passed as pos, the whole string will be searched.

# Declarations

constexpr size_type rfind( basic_string_view v, size_type pos = npos ) const noexcept;

(since C++17)

constexpr size_type rfind( CharT ch, size_type pos = npos ) const noexcept;

(since C++17)

constexpr size_type rfind( const CharT* s, size_type pos, size_type count ) const;

(since C++17)

constexpr size_type rfind( const CharT* s, size_type pos = npos ) const;

(since C++17)

# Parameters

# Return value

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

# 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))
        && (0 == "AB CD EF"sv.rfind("AB", 0))
        && (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