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

      From cppreference.com
      <cpp‎ |string‎ |basic string view
       
       
       
      std::basic_string_view
       
      constexpr const_reference at( size_type pos)const;
      (since C++17)

      Returns aconst reference to the character at specified locationpos. Bounds checking is performed, exception of typestd::out_of_range will be thrown on invalid access.

      Contents

      [edit]Parameters

      pos - position of the character to return

      [edit]Return value

      Const reference to the requested character.

      [edit]Exceptions

      Throwsstd::out_of_range ifpos>= size().

      [edit]Complexity

      Constant.

      [edit]Example

      Run this code
      #include <iostream>#include <stdexcept>#include <string_view> int main(){std::string_view str_view("abcdef"); try{for(std::size_t i=0;true;++i)std::cout<< i<<": "<< str_view.at(i)<<'\n';}catch(conststd::out_of_range& e){std::cout<<"Whooops. Index is out of range.\n";std::cout<< e.what()<<'\n';}}

      Possible output:

      0: a1: b2: c3: d4: e5: f6: Whooops. Index is out of range.basic_string_view::at: __pos (which is 6) >= this->size() (which is 6)

      [edit]See also

      accesses the specified character
      (public member function)[edit]
      accesses the specified character with bounds checking
      (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/at&oldid=152752"

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