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

 

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Technical specifications

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Strings library

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Classes

basic_string

basic_string_view (C++17)

char_traits

 

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 find_last_of( basic_string_view v, size_type pos = npos ) const noexcept;	(1)	(since C++17)
constexpr size_type find_last_of( CharT c, size_type pos = npos ) const noexcept;	(2)	(since C++17)
constexpr size_type find_last_of( const CharT* s, size_type pos, size_type count ) const;	(3)	(since C++17)
constexpr size_type find_last_of( const CharT* s, size_type pos = npos ) const;	(4)	(since C++17)

Finds the last character equal to one of characters in the given character sequence. Exact search algorithm is not specified. The search considers only the interval [0; pos]. If the character is not present in the interval, npos will be returned.

1) Finds the last occurence of any of the characters of v in this view, ending at position pos.

2) Equivalent to find_last_of(basic_string_view(std::addressof(c), 1), pos).

3) Equivalent to find_last_of(basic_string_view(s, count), pos).

4) Equivalent to find_last_of(basic_string_view(s), pos).

Parameters

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

Return value

Position of the last occurrence of any character of the substring, or npos if no such character is found.

Complexity

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

Example

Run this code

#include <string_view>
#include <iostream>
 
int main()
{
  using namespace std::literals;
  constexpr auto N = std::string_view::npos;
 
  static_assert(
    5 == "delete"sv.find_last_of("cdef"sv) &&
      //       └────────────────────┘
    N == "double"sv.find_last_of("fghi"sv) &&
      //
    0 == "else"sv.find_last_of("bcde"sv, 2 /* pos [0..2]: "els" */) &&
      //  └────────────────────────┘
    N == "explicit"sv.find_last_of("abcd"sv, 4 /* pos [0..4]: "expli" */) &&
      //
    3 == "extern"sv.find_last_of('e') &&
      //     └────────────────────┘
    N == "false"sv.find_last_of('x') &&
      //
    0 == "inline"sv.find_last_of('i', 2 /* pos [0..2]: "inl" */) &&
      //  └───────────────────────┘
    N == "mutable"sv.find_last_of('a', 2 /* pos [0..2]: "mut" */) &&
      //
    3 == "namespace"sv.find_last_of("cdef", 3 /* pos [0..3]: "name" */, 3 /* "cde" */) &&
      //     └─────────────────────────┘
    N == "namespace"sv.find_last_of("cdef", 3 /* pos [0..3]: "name" */, 2 /* "cd" */)
  );
 
  std::cout << "All tests passed.\n";
}

Output:

All tests passed.

See also

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