std::basic_string_view<CharT,Traits>::rfind
| constexpr size_type rfind(basic_string_view v, size_type pos = npos) const noexcept; | (1) | (since C++17) | 
| constexpr size_type rfind(CharT c, 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.
1) Finds the last occurence of 
 v in this view, starting at position pos.
2) Equivalent to 
 rfind(basic_string_view(std::addressof(c), 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.
See also
| find characters in the view (public member function) | |
| find first occurrence of characters (public member function) | |
| find last occurrence of characters (public member function) | |
| find first absence of characters (public member function) | |
| find last absence of characters (public member function) | 
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