use of algorithms in function cause ERROR: no instance of overloaded function

[wolle]

I have never tried it before, but std::span of C++ 20 seems a nice way of using C-style arrays with the standard library. An advantage is that it works with std::vector and std::array too.

https://www.modernescpp.com/index.php/c-20-std-span

(In C++ 23, there is also the std::mdspan. It will allow you to view a one-dimensional array (std::vector, std::array, or C-style array) as a multidimensional array.)

https://www.youtube.com/watch?v=aFCLmQEkPUw

#include <iostream>
#include <algorithm>
#include <span>
#include <vector>
#include <array>

constexpr size_t ELEMENTS { 8 };

void show(std::span<int> arr) {
	for (const auto& c : arr)
		std::cout << c;

	std::cout << '\n';
}

void bool_element_option_03(std::span<int> arr_value, std::span<int> arr_copy_value) {
	std::copy(std::begin(arr_value), std::end(arr_value), std::begin(arr_copy_value));
	std::sort(std::rbegin(arr_copy_value), std::rend(arr_copy_value));

	std::cout << "\nReverse sorted:\n";
	show(arr_copy_value);
}

void test() {
	int arr_value[ELEMENTS] { 1, 2, 9, 4, 5, 6, 7, 8 };
	int arr_copy_value[ELEMENTS] {};

		// works too
//	std::vector<int> arr_value { 1, 2, 9, 4, 5, 6, 7, 8 };
//	std::vector<int> arr_copy_value(arr_value.size(), {});

		// works too
//	std::array<int, ELEMENTS> arr_value { 1, 2, 9, 4, 5, 6, 7, 8 };
//	std::array<int, ELEMENTS> arr_copy_value {};

	std::cout << "\nOriginal order:\n";
	show(arr_value);
	bool_element_option_03(arr_value, arr_copy_value);
}