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

      From cppreference.com
      <cpp‎ |string‎ |basic string view
       
       
       
      std::basic_string_view
       
      constexpr size_type find( basic_string_view v, size_type pos=0)constnoexcept;
      (1)(since C++17)
      constexpr size_type find( CharT ch, size_type pos=0)constnoexcept;
      (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 ofv in this view, starting at positionpos.
      2) Equivalent tofind(basic_string_view(std::addressof(ch),1), pos).
      3) Equivalent tofind(basic_string_view(s, count), pos).
      4) Equivalent tofind(basic_string_view(s), pos).

      Contents

      [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, ornpos if no such substring is found.

      [edit]Complexity

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

      [edit]Example

      Run this code
      #include <string_view> int main(){usingnamespace std::literals; constexprauto 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

      find the last occurrence of a substring
      (public member function)[edit]
      find first occurrence of characters
      (public member function)[edit]
      find last occurrence of characters
      (public member function)[edit]
      find first absence of characters
      (public member function)[edit]
      find last absence of characters
      (public member function)[edit]
      finds the first occurrence of the given substring
      (public member function ofstd::basic_string<CharT,Traits,Allocator>)[edit]
      Retrieved from "https://en.cppreference.com/mwiki/index.php?title=cpp/string/basic_string_view/find&oldid=152783"

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