std::basic_string_view<CharT,Traits>::find - cppreference.com (original) (raw)

constexpr size_type find( basic_string_view v, size_type pos = 0 ) const noexcept; (1) (since C++17)
constexpr size_type find( CharT ch, size_type pos = 0 ) const noexcept; (2) (since C++17)
constexpr size_type find( const CharT* s, size_type pos, size_type count ) const; (3) (since C++17)
constexpr size_type find( const CharT* s, size_type pos = 0 ) const; (4) (since C++17)

Finds the first substring equal to the given character sequence.

  1. Finds the first occurence of v in this view, starting at position pos.

  2. Equivalent to find(basic_string_view(std::addressof(ch), 1), pos).

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

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

[edit] 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

[edit] Return value

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

[edit] Complexity

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

[edit] Example

#include   int main() { using namespace std::literals;   constexpr auto str{" long long int;"sv};   static_assert( 1 == str.find("long"sv) && "<- find(v , pos = 0)" && 6 == str.find("long"sv, 2) && "<- find(v , pos = 2)" && 0 == str.find(' ') && "<- find(ch, pos = 0)" && 2 == str.find('o', 1) && "<- find(ch, pos = 1)" && 2 == str.find("on") && "<- find(s , pos = 0)" && 6 == str.find("long double", 5, 4) && "<- find(s , pos = 5, count = 4)" );   static_assert(str.npos == str.find("float")); }

[edit] See also

rfind find the last occurrence of a substring (public member function) [edit]
find_first_of find first occurrence of characters (public member function) [edit]
find_last_of find last occurrence of characters (public member function) [edit]
find_first_not_of find first absence of characters (public member function) [edit]
find_last_not_of find last absence of characters (public member function) [edit]
find finds the first occurrence of the given substring (public member function of std::basic_string<CharT,Traits,Allocator>) [edit]