boost_variant 0.1.0

Boost C++ library boost_variant packaged using Zanbil
Documentation 
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// Copyright (c) 2017
// Mikhail Maximov
//
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)

#include "boost/config.hpp"
#include "boost/core/lightweight_test.hpp"

#ifdef __cpp_inheriting_constructors
// Test is based on reported issue:
// https://svn.boost.org/trac/boost/ticket/12680
// GCC 6 crashed, trying to determine is boost::recursive_wrapper<Node>
// is_noexcept_move_constructible

#include <string>

#include <boost/variant.hpp>
#include <boost/array.hpp>

struct Leaf { };
struct Node;

typedef boost::variant<Leaf, boost::recursive_wrapper<Node>> TreeBase;

struct Tree : TreeBase {
  using TreeBase::TreeBase;

  template <typename Iter>
  static Tree Create(Iter /*first*/, Iter /*last*/) { return Leaf{}; }
};

struct Node {
  Tree left, right;
};


// Test from https://svn.boost.org/trac/boost/ticket/7120
template<class Node>
struct node1_type;

struct var_type;

using var_base = boost::variant<int,
  boost::recursive_wrapper<node1_type<var_type>>
>;

template<class Node>
struct node1_type {
  boost::array<Node, 1> children;
};

struct var_type : var_base {
  using var_base::var_base;
};

void run() {
  std::string input{"abracadabra"};
  const Tree root = Tree::Create(input.begin(), input.end());
  (void)root; // prevents unused variable warning

  var_type v1 = 1;
  (void)v1;
}

#else // #!ifdef __cpp_inheriting_constructors
// if compiler does not support inheriting constructors - does nothing
void run() {}
#endif

int main()
{
    run();
    return boost::report_errors();
}