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std::span::front(3)	       C++ Standard Libary	     std::span::front(3)

NAME
     std::span::front - std::span::front

Synopsis
	constexpr reference front() const;  (since C++20)

	Returns a reference to the first element in the span.

	Calling front on an empty span results in undefined behavior.

Parameters
	(none)

Return value
	A reference to the first element.

Complexity
	Constant.

Notes
	For a span c, the expression c.front() is equivalent to *c.begin().

Example
     // Run this code

      #include <iostream>
      #include <span>

      void print(std::span<const int> const data)
      {
	  for (auto offset{0U}; offset != data.size(); ++offset)
	      std::cout << data.subspan(offset).front() << ' ';
	  std::cout << '\n';
      }

      int main()
      {
	  constexpr int data[]{0, 1, 2, 3, 4, 5, 6};
	  print({data, 4});
      }

Output:
      0 1 2 3

See also
	back access the last element
	     (public member function)

http://cppreference.com 	   2024.06.10		     std::span::front(3)
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