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#include <array>
#include <span>
#include <stdio.h>
#include <string>
#include <vector>
template <class T, size_t N>
void by_ref_and_ptr(std::span<T, N> &ref, std::span<T, N> *ptr) {
printf("Stop here to check by ref");
return;
}
int main() {
std::array numbers = {1, 12, 123, 1234, 12345};
using dynamic_string_span = std::span<std::string>;
// Test span of ints
// Full view of numbers with static extent
std::span numbers_span = numbers;
printf("break here");
by_ref_and_ptr(numbers_span, &numbers_span);
// Test spans of strings
std::vector<std::string> strings{"goofy", "is", "smart", "!!!"};
strings.reserve(strings.size() + 1);
// Partial view of strings with dynamic extent
dynamic_string_span strings_span{std::span{strings}.subspan(2)};
auto strings_span_it = strings_span.begin();
printf("break here");
// Vector size doesn't increase, span should
// print unchanged and the strings_span_it
// remains valid
strings.emplace_back("???");
printf("break here");
// Now some empty spans
std::span<int, 0> static_zero_span;
std::span<int> dynamic_zero_span;
// Multiple spans
std::array span_arr{strings_span, strings_span};
std::span<std::span<std::string>, 2> nested = span_arr;
printf("break here");
return 0; // break here
}
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