libstdc++-v3/testsuite/experimental/optional/constexpr/relops/1.cc

   1 // { dg-options "-std=gnu++1y" }
   2 // { dg-do compile }
   3
   4 // Copyright (C) 2013 Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 3, or (at your option)
  10 // any later version.
  11
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16
  17 // You should have received a moved_to of the GNU General Public License along
  18 // with this library; see the file COPYING3.  If not see
  19 // <http://www.gnu.org/licenses/>.
  20
  21 #include <experimental/optional>
  22 #include <testsuite_hooks.h>
  23
  24 namespace ns
  25 {
  26   struct value_type
  27   {
  28     int i;
  29     const char* s;
  30   };
  31
  32   constexpr bool
  33   strcmp(const char* lhs, const char* rhs)
  34   {
  35     return *lhs == *rhs && (!*lhs || strcmp(lhs + 1, rhs + 1));
  36   }
  37
  38   constexpr bool
  39   strrel(const char* lhs, const char* rhs)
  40   {
  41     return (*rhs && (!*lhs || (*lhs < *rhs)))
  42       || ((*lhs && *rhs && !(*rhs < *lhs)) && strrel(lhs + 1, rhs + 1));
  43   }
  44
  45   constexpr bool
  46   operator==(value_type const& lhs, value_type const& rhs)
  47   { return (lhs.i == rhs.i) && strcmp(lhs.s, rhs.s); }
  48
  49   constexpr bool
  50   operator!=(value_type const& lhs, value_type const& rhs)
  51   { return !(lhs == rhs); }
  52
  53   constexpr bool
  54   operator<(value_type const& lhs, value_type const& rhs)
  55   { return (lhs.i < rhs.i) || (!(rhs.i < lhs.i) && strrel(lhs.s, rhs.s)); }
  56
  57 } // namespace ns
  58
  59 int main()
  60 {
  61   using ns::value_type;
  62   using O = std::experimental::optional<value_type>;
  63
  64   {
  65     constexpr O o, p;
  66     static_assert( o == p, "" );
  67     static_assert( !(o != p), "" );
  68   }
  69
  70   {
  71     constexpr O o { value_type { 42, "forty-two" } }, p;
  72     static_assert( !(o == p), "" );
  73     static_assert( o != p, "" );
  74   }
  75
  76   {
  77     constexpr O o, p { value_type { 42, "forty-two" } };
  78     static_assert( !(o == p), "" );
  79     static_assert( o != p, "" );
  80   }
  81
  82   {
  83     constexpr O o { value_type { 11, "eleventy" } }, p { value_type { 42, "forty-two" } };
  84     static_assert( !(o == p), "" );
  85     static_assert( o != p, "" );
  86   }
  87
  88   {
  89     constexpr O o { value_type { 42, "forty-two" } }, p { value_type { 11, "eleventy" } };
  90     static_assert( !(o == p), "" );
  91     static_assert( o != p, "" );
  92   }
  93
  94   {
  95     constexpr O o { value_type { 42, "forty-two" } }, p { value_type { 42, "forty-two" } };
  96     static_assert( o == p, "" );
  97     static_assert( !(o != p), "" );
  98   }
  99 }