/*============================================================================= | |
Copyright (c) 2001-2011 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(SPIRIT_SEQUENTIAL_OR_MARCH_12_2007_1130PM) | |
#define SPIRIT_SEQUENTIAL_OR_MARCH_12_2007_1130PM | |
#if defined(_MSC_VER) | |
#pragma once | |
#endif | |
#include <boost/spirit/home/qi/meta_compiler.hpp> | |
#include <boost/spirit/home/qi/detail/pass_function.hpp> | |
#include <boost/spirit/home/qi/detail/attributes.hpp> | |
#include <boost/spirit/home/support/detail/what_function.hpp> | |
#include <boost/spirit/home/support/algorithm/any_if_ns.hpp> | |
#include <boost/fusion/include/as_vector.hpp> | |
#include <boost/fusion/include/for_each.hpp> | |
namespace boost { namespace spirit | |
{ | |
/////////////////////////////////////////////////////////////////////////// | |
// Enablers | |
/////////////////////////////////////////////////////////////////////////// | |
template <> | |
struct use_operator<qi::domain, proto::tag::logical_or> // enables || | |
: mpl::true_ {}; | |
template <> | |
struct flatten_tree<qi::domain, proto::tag::logical_or> // flattens || | |
: mpl::true_ {}; | |
}} | |
namespace boost { namespace spirit { namespace qi | |
{ | |
template <typename Elements> | |
struct sequential_or : nary_parser<sequential_or<Elements> > | |
{ | |
template <typename Context, typename Iterator> | |
struct attribute | |
{ | |
// Put all the element attributes in a tuple, | |
// wrapping each element in a boost::optional | |
typedef typename traits::build_attribute_sequence< | |
Elements, Context, traits::sequential_or_attribute_transform | |
, Iterator, qi::domain | |
>::type all_attributes; | |
// Now, build a fusion vector over the attributes. Note | |
// that build_fusion_vector 1) removes all unused attributes | |
// and 2) may return unused_type if all elements have | |
// unused_type(s). | |
typedef typename | |
traits::build_fusion_vector<all_attributes>::type | |
type; | |
}; | |
sequential_or(Elements const& elements) | |
: elements(elements) {} | |
template <typename Iterator, typename Context | |
, typename Skipper, typename Attribute> | |
bool parse(Iterator& first, Iterator const& last | |
, Context& context, Skipper const& skipper | |
, Attribute& attr_) const | |
{ | |
typedef traits::attribute_not_unused<Context, Iterator> predicate; | |
detail::pass_function<Iterator, Context, Skipper> | |
f(first, last, context, skipper); | |
// wrap the attribute in a tuple if it is not a tuple | |
typename traits::wrap_if_not_tuple<Attribute>::type attr(attr_); | |
// return true if *any* of the parsers succeed | |
// (we use the non-short-circuiting version: any_if_ns | |
// to force all elements to be tested) | |
return spirit::any_if_ns(elements, attr, f, predicate()); | |
} | |
template <typename Context> | |
info what(Context& context) const | |
{ | |
info result("sequential-or"); | |
fusion::for_each(elements, | |
spirit::detail::what_function<Context>(result, context)); | |
return result; | |
} | |
Elements elements; | |
}; | |
/////////////////////////////////////////////////////////////////////////// | |
// Parser generators: make_xxx function (objects) | |
/////////////////////////////////////////////////////////////////////////// | |
template <typename Elements, typename Modifiers> | |
struct make_composite<proto::tag::logical_or, Elements, Modifiers> | |
: make_nary_composite<Elements, sequential_or> | |
{}; | |
}}} | |
namespace boost { namespace spirit { namespace traits | |
{ | |
/////////////////////////////////////////////////////////////////////////// | |
// We specialize this for sequential_or (see support/attributes.hpp). | |
// For sequential_or, we only wrap the attribute in a tuple IFF | |
// it is not already a fusion tuple. | |
template <typename Elements, typename Attribute> | |
struct pass_attribute<qi::sequential_or<Elements>, Attribute> | |
: wrap_if_not_tuple<Attribute> {}; | |
/////////////////////////////////////////////////////////////////////////// | |
template <typename Elements> | |
struct has_semantic_action<qi::sequential_or<Elements> > | |
: nary_has_semantic_action<Elements> {}; | |
/////////////////////////////////////////////////////////////////////////// | |
template <typename Elements, typename Attribute, typename Context | |
, typename Iterator> | |
struct handles_container<qi::sequential_or<Elements>, Attribute, Context | |
, Iterator> | |
: nary_handles_container<Elements, Attribute, Context, Iterator> {}; | |
}}} | |
#endif |