llvm/libcxx/test/std/containers/views/mdspan/mdspan/element_type.verify.cpp

//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20

// <mdspan>

// template<class ElementType, class Extents, class LayoutPolicy = layout_right, class AccessorPolicy = default_accessor>
// class mdspan;
//
// Mandates:
//   - ElementType is a complete object type that is neither an abstract class type nor an array type.
//   - is_same_v<ElementType, typename AccessorPolicy::element_type> is true.

#include <mdspan>

class AbstractClass {
public:
  virtual void method() = 0;
};

void not_abstract_class() {
  // expected-error-re@*:* {{static assertion failed {{.*}}mdspan: ElementType template parameter may not be an abstract class}}
  [[maybe_unused]] std::mdspan<AbstractClass, std::extents<int>> m;
}

void not_array_type() {
  // expected-error-re@*:* {{static assertion failed {{.*}}mdspan: ElementType template parameter may not be an array type}}
  [[maybe_unused]] std::mdspan<int[5], std::extents<int>> m;
}

void element_type_mismatch() {
  // expected-error-re@*:* {{static assertion failed {{.*}}mdspan: ElementType template parameter must match AccessorPolicy::element_type}}
  [[maybe_unused]] std::mdspan<int, std::extents<int>, std::layout_right, std::default_accessor<const int>> m;
}