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      std::basic_string_view<CharT,Traits>::size,std::basic_string_view<CharT,Traits>::length

      From cppreference.com
      <cpp‎ |string‎ |basic string view
       
       
       
      std::basic_string_view
       
      constexpr size_type size()constnoexcept;
      (since C++17)
      constexpr size_type length()constnoexcept;
      (since C++17)

      Returns the number ofCharT elements in the view, i.e.std::distance(begin(), end()).

      Contents

      [edit]Parameters

      (none)

      [edit]Return value

      The number ofCharT elements in the view.

      [edit]Complexity

      Constant.

      [edit]Example

      Run this code
      #include <iostream>#include <string_view> // Print a string surrounded by single quotes, its// length and whether it is considered empty.void check_string(std::string_view ref){std::cout<<std::boolalpha<<"'"<< ref<<"' has "<< ref.size()<<" character(s); emptiness: "<< ref.empty()<<'\n';} int main(int argc,char**argv){// An empty string    check_string(""); // Almost always not empty: argv[0]if(argc>0)        check_string(argv[0]);}

      Possible output:

      '' has 0 character(s); emptiness: true'./a.out' has 7 character(s); emptiness: false

      [edit]See also

      checks whether the view is empty
      (public member function)[edit]
      returns the maximum number of characters
      (public member function)[edit]
      returns the number of characters
      (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/size&oldid=145084"

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