libcxx/test/std/containers/views/span.sub/first.fail.cpp

   1 // -*- C++ -*-
   2 //===------------------------------ span ---------------------------------===//
   3 //
   4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   5 // See https://llvm.org/LICENSE.txt for license information.
   6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   7 //
   8 //===---------------------------------------------------------------------===//
   9 // UNSUPPORTED: c++03, c++11, c++14, c++17
  10
  11 // <span>
  12
  13 // template<size_t Count>
  14 //  constexpr span<element_type, Count> first() const;
  15 //
  16 // constexpr span<element_type, dynamic_extent> first(size_type count) const;
  17 //
  18 //  Requires: Count <= size().
  19
  20 #include <span>
  21
  22 #include "test_macros.h"
  23
  24 constexpr int carr[] = {1, 2, 3, 4};
  25
  26 int main(int, char**) {
  27   std::span<const int, 4> sp(carr);
  28
  29   //  Count too large
  30   {
  31     [[maybe_unused]] auto s1 = sp.first<5>(); // expected-error-re@span:* {{static_assert failed{{( due to requirement '.*')?}} "Count out of range in span::first()"}}
  32   }
  33
  34   //  Count numeric_limits
  35   {
  36     [[maybe_unused]] auto s1 = sp.first<std::size_t(-1)>(); // expected-error-re@span:* {{static_assert failed{{( due to requirement '.*')?}} "Count out of range in span::first()"}}
  37   }
  38
  39   return 0;
  40 }