NAME¶

std::basic_string_view::find_last_of - std::basic_string_view::find_last_of

Synopsis¶

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

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