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std::basic_string_view::at(3)  C++ Standard Libary std::basic_string_view::at(3)

NAME
     std::basic_string_view::at - std::basic_string_view::at

Synopsis
	constexpr const_reference at( size_type pos ) const;  (since C++17)

	Returns  a  const  reference to the character at specified location pos.
     Bounds
	checking is performed,	exception  of  type  std::out_of_range	will  be
     thrown on invalid
	access.

Parameters
	pos - position of the character to return

Return value
	Const reference to the requested character.

Exceptions
	Throws std::out_of_range if pos >= size().

Complexity
	Constant.

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 (const std::out_of_range& e)
	  {
	      std::cout << "Whooops. Index is out of range.\n";
	      std::cout << e.what() << '\n';
	  }
      }

Possible output:
      0: a
      1: b
      2: c
      3: d
      4: e
      5: f
      6: Whooops. Index is out of range.
      basic_string_view::at: __pos (which is 6) >= this->size() (which is 6)

See also
	operator[] accesses the specified character
		   (public member function)
		   accesses the specified character with bounds checking
	at	   (public member function of std::basic_string<CharT,Traits,Al-
     locator>)

http://cppreference.com 	   2024.06.10	   std::basic_string_view::at(3)
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