libcxx/test/std/containers/sequences/array/begin.pass.cpp

   1 //===----------------------------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 // <array>
  10
  11 // iterator begin();
  12
  13 #include <array>
  14 #include <cassert>
  15
  16 #include "test_macros.h"
  17
  18 // std::array is explicitly allowed to be initialized with A a = { init-list };.
  19 // Disable the missing braces warning for this reason.
  20 #include "disable_missing_braces_warning.h"
  21
  22 struct NoDefault {
  23   NoDefault(int) {}
  24 };
  25
  26
  27 int main(int, char**)
  28 {
  29     {
  30         typedef double T;
  31         typedef std::array<T, 3> C;
  32         C c = {1, 2, 3.5};
  33         C::iterator i;
  34         i = c.begin();
  35         assert(*i == 1);
  36         assert(&*i == c.data());
  37         *i = 5.5;
  38         assert(c[0] == 5.5);
  39     }
  40     {
  41       typedef NoDefault T;
  42       typedef std::array<T, 0> C;
  43       C c = {};
  44       C::iterator ib, ie;
  45       ib = c.begin();
  46       ie = c.end();
  47       assert(ib == ie);
  48       LIBCPP_ASSERT(ib != nullptr);
  49       LIBCPP_ASSERT(ie != nullptr);
  50     }
  51
  52   return 0;
  53 }