| /*============================================================================= |
| Copyright (c) 2001-2014 Joel de Guzman |
| |
| 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) |
| =============================================================================*/ |
| #if !defined(BOOST_SPIRIT_X3_ALTERNATIVE_JAN_07_2013_1131AM) |
| #define BOOST_SPIRIT_X3_ALTERNATIVE_JAN_07_2013_1131AM |
| |
| #include <boost/spirit/home/x3/support/traits/attribute_of_binary.hpp> |
| #include <boost/spirit/home/x3/core/parser.hpp> |
| #include <boost/spirit/home/x3/operator/detail/alternative.hpp> |
| |
| #include <boost/variant/variant_fwd.hpp> |
| |
| namespace boost { namespace spirit { namespace x3 |
| { |
| template <typename Left, typename Right> |
| struct alternative : binary_parser<Left, Right, alternative<Left, Right>> |
| { |
| typedef binary_parser<Left, Right, alternative<Left, Right>> base_type; |
| |
| constexpr alternative(Left const& left, Right const& right) |
| : base_type(left, right) {} |
| |
| template <typename Iterator, typename Context, typename RContext> |
| bool parse( |
| Iterator& first, Iterator const& last |
| , Context const& context, RContext& rcontext, unused_type) const |
| { |
| return this->left.parse(first, last, context, rcontext, unused) |
| || this->right.parse(first, last, context, rcontext, unused); |
| } |
| |
| template <typename Iterator, typename Context |
| , typename RContext, typename Attribute> |
| bool parse( |
| Iterator& first, Iterator const& last |
| , Context const& context, RContext& rcontext, Attribute& attr) const |
| { |
| return detail::parse_alternative(this->left, first, last, context, rcontext, attr) |
| || detail::parse_alternative(this->right, first, last, context, rcontext, attr); |
| } |
| }; |
| |
| template <typename Left, typename Right> |
| constexpr alternative< |
| typename extension::as_parser<Left>::value_type |
| , typename extension::as_parser<Right>::value_type> |
| operator|(Left const& left, Right const& right) |
| { |
| return { as_parser(left), as_parser(right) }; |
| } |
| }}} |
| |
| namespace boost { namespace spirit { namespace x3 { namespace traits |
| { |
| template <typename Left, typename Right, typename Context> |
| struct attribute_of<x3::alternative<Left, Right>, Context> |
| : x3::detail::attribute_of_binary<boost::variant, x3::alternative, Left, Right, Context> {}; |
| }}}} |
| |
| #endif |