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std::basic_string::data(3)    C++ Standard Libary   std::basic_string::data(3)

NAME
       std::basic_string::data - std::basic_string::data

Synopsis
	  const	CharT* data() const;				(until C++11)
	  const	CharT* data() const noexcept;			(since C++11)
								(until C++20)
	  constexpr const CharT* data()	const noexcept;	(1)	(since C++20)
	  CharT*			data()			     noexcept;
       (since C++17)
							    (2)
       (until C++20)
	  constexpr	       CharT*		  data()	     noexcept;
       (since C++20)

	  Returns a pointer to the underlying array serving as character stor-
       age. The	pointer
	  is such that the range

	  [data(); data() + size())
	  (until C++11)
	  [data(); data() + size()]
	  (since C++11)

	  is valid and the values in it	correspond to the values stored	in the
       string.

	  The returned array is	not required to	be null-terminated.
										 (un-
       til C++11)
	  If  empty()  returns	true,  the  pointer is a non-null pointer that
       should
	  not be dereferenced.
	  The returned array is	null-terminated, that is, data() and c_str()
	  perform the same function.
										 (since
       C++11)
	  If empty() returns true, the pointer points to a single null
	  character.

	  The pointer obtained from data() may be invalidated by:

	    * Passing a	non-const reference to the string to any standard  li-
       brary function, or
	    *  Calling non-const member	functions on the string, excluding op-
       erator[](), at(),
	      front(), back(), begin(),	end(), rbegin(), rend().

	  1) Modifying the character array accessed through the	const overload
       of data has
	  undefined behavior.
	  2)  Modifying	  the	past-the-end   null   terminator   stored   at
       data()+size() to	any value
	  other	than CharT() has undefined behavior.

Parameters
	  (none)

Return value
	  A pointer to the underlying character	storage.

	  data()[i]   ==   operator[](i)   for	 every	 i   in	 [0,  size()).
       (until C++11)
	  data() + i ==	 std::addressof(operator[](i))	for  every  i  in  [0,
       (since C++11)
	  size()].

Complexity
	  Constant.

Example
       // Run this code

	#include <algorithm>
	#include <cassert>
	#include <cstring>
	#include <string>

	int main()
	{
	  std::string const s("Emplary");
	  assert(s.size() == std::strlen(s.data()));
	  assert(std::equal(s.begin(), s.end(),	s.data()));
	  assert(std::equal(s.data(), s.data() + s.size(), s.begin()));
	  assert(0 == *(s.data() + s.size()));
	}

See also
	  front	  accesses the first character
	  (C++11) (public member function)
	  back	  accesses the last character
	  (C++11) (public member function)
	  c_str	   returns a non-modifiable standard C character array version
       of the string
		  (public member function)
	  data	  returns a pointer to the first character of a	view
	  (C++17)      (public	    member	function      of      std::ba-
       sic_string_view<CharT,Traits>)

http://cppreference.com		  2022.07.31	    std::basic_string::data(3)

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