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

NAME
       std::span::begin	- std::span::begin

Synopsis
	  constexpr iterator begin() const noexcept;

	  Returns an iterator to the first element of the span.

	  If the span is empty,	the returned iterator will be equal to end().

	  range-begin-end.svg

Parameters
	  (none)

Return value
	  Iterator to the first	element.

Complexity
	  Constant.

Example
       // Run this code

	#include <span>
	#include <iostream>

	void print(std::span<const int>	sp)
	{
	    for(auto it	= sp.begin(); it != sp.end(); ++it) {
		std::cout << *it << ' ';
	    }
	    std::cout << '\n';
	}

	void transmogrify(std::span<int> sp)
	{
	    if (!sp.empty()) {
		std::cout << *sp.begin() << '\n';
		*sp.begin() = 2;
	    }
	}

	int main()
	{
	    int	array[]	{ 1, 3,	4, 5 };
	    print(array);
	    transmogrify(array);
	    print(array);
	}

Output:
	1 3 4 5
	1
	2 3 4 5

See also
	  end	  returns an iterator to the end
	  (C++20) (public member function)
	  begin
	  cbegin  returns an iterator to the beginning of a container or array
	  (C++11) (function template)
	  (C++14)

http://cppreference.com		  2022.07.31		   std::span::begin(3)

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<https://man.freebsd.org/cgi/man.cgi?query=std::span::begin&sektion=3&manpath=FreeBSD+Ports+15.0>

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