std::basic_string_view::find_last_not_of
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                    < cpp | string | basic string view
                    
                                                            
                    | constexpr size_type  find_last_not_of(basic_string_view v, size_type pos = npos) const; | (1) | (since C++17) | 
| constexpr size_type find_last_not_of(CharT c, size_type pos = npos) const; | (2) | (since C++17) | 
| constexpr size_type find_last_not_of(const CharT* s, size_type pos, size_type count) const; | (3) | (since C++17) | 
| constexpr size_type find_last_not_of(const CharT* s, size_type pos = npos) const; | (4) | (since C++17) | 
Finds the last character not equal to any of the characters in the given character sequence.
1) Finds the last character not equal to any of the characters of 
v in this view, starting at position pos.2) Equivalent to find_last_not_of(basic_string_view(&c, 1), pos).
3) Equivalent to find_last_not_of(basic_string_view(s, count), pos).
4) Equivalent to find_last_not_of(basic_string_view(s), pos).
Parameters
| v | - | view to search for | 
| pos | - | position at which to start the search | 
| count | - | length of the string of characters to compare | 
| s | - | pointer to a string of characters to compare | 
| ch | - | character to compare | 
Return value
Position of the last character not equal to any of the characters in the given string, or npos if no such character is found.
Exceptions
1-2)noexcept specification:  
noexcept
  Complexity
O(size() * v.size()) at worst.
See also
| find characters in the view (public member function) | |
| find the last occurrence of a substring (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) |