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// -*- C++ -*-
//===------------------------------ span ---------------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===---------------------------------------------------------------------===//
// UNSUPPORTED: c++98, c++03, c++11, c++14, c++17

// <span>

// constexpr span(pointer ptr, index_type count);
// Requires: [ptr, ptr + count) shall be a valid range.
//  If extent is not equal to dynamic_extent, then count shall be equal to extent.
//

#include <span>
#include <cassert>
#include <string>

#include "test_macros.h"


               int   arr[] = {1,2,3};
const          int  carr[] = {4,5,6};
      volatile int  varr[] = {7,8,9};
const volatile int cvarr[] = {1,3,5};

int main ()
{
//  We can't check that the size doesn't match - because that's a runtime property
//  std::span<int, 2>   s1(arr, 3);

//  Type wrong
    {
    std::span<float>    s1(arr, 3);   // expected-error {{no matching constructor for initialization of 'std::span<float>'}}
    std::span<float, 3> s2(arr, 3);   // expected-error {{no matching constructor for initialization of 'std::span<float, 3>'}}
    }

//  CV wrong (dynamically sized)
    {
    std::span<               int> s1{ carr, 3}; // expected-error {{no matching constructor for initialization of 'std::span<int>'}}
    std::span<               int> s2{ varr, 3}; // expected-error {{no matching constructor for initialization of 'std::span<int>'}}
    std::span<               int> s3{cvarr, 3}; // expected-error {{no matching constructor for initialization of 'std::span<int>'}}
    std::span<const          int> s4{ varr, 3}; // expected-error {{no matching constructor for initialization of 'std::span<const int>'}}
    std::span<const          int> s5{cvarr, 3}; // expected-error {{no matching constructor for initialization of 'std::span<const int>'}}
    std::span<      volatile int> s6{ carr, 3}; // expected-error {{no matching constructor for initialization of 'std::span<volatile int>'}}
    std::span<      volatile int> s7{cvarr, 3}; // expected-error {{no matching constructor for initialization of 'std::span<volatile int>'}}
    }

//  CV wrong (statically sized)
    {
    std::span<               int,3> s1{ carr, 3};   // expected-error {{no matching constructor for initialization of 'std::span<int, 3>'}}
    std::span<               int,3> s2{ varr, 3};   // expected-error {{no matching constructor for initialization of 'std::span<int, 3>'}}
    std::span<               int,3> s3{cvarr, 3};   // expected-error {{no matching constructor for initialization of 'std::span<int, 3>'}}
    std::span<const          int,3> s4{ varr, 3};   // expected-error {{no matching constructor for initialization of 'std::span<const int, 3>'}}
    std::span<const          int,3> s5{cvarr, 3};   // expected-error {{no matching constructor for initialization of 'std::span<const int, 3>'}}
    std::span<      volatile int,3> s6{ carr, 3};   // expected-error {{no matching constructor for initialization of 'std::span<volatile int, 3>'}}
    std::span<      volatile int,3> s7{cvarr, 3};   // expected-error {{no matching constructor for initialization of 'std::span<volatile int, 3>'}}
    }
}