82 lines
2.7 KiB
C++
Executable File
82 lines
2.7 KiB
C++
Executable File
/*=============================================================================
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Copyright (c) 2001-2008 Hartmut Kaiser
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Distributed under the Boost Software License, Version 1.0. (See accompanying
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file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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=============================================================================*/
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#if !defined(SPIRIT_ALTERNATIVE_FUNCTION_APR_23_2007_1046AM)
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#define SPIRIT_ALTERNATIVE_FUNCTION_APR_23_2007_1046AM
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#include <boost/spirit/home/qi/domain.hpp>
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#include <boost/spirit/home/support/unused.hpp>
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#include <boost/spirit/home/support/attribute_of.hpp>
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#include <boost/variant.hpp>
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namespace boost { namespace spirit { namespace qi { namespace detail
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{
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template <typename Iterator, typename Context, typename Skipper,
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typename Attribute>
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struct alternative_function
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{
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alternative_function(
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Iterator& first, Iterator const& last, Context& context,
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Skipper const& skipper, Attribute& attr)
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: first(first), last(last), context(context), skipper(skipper),
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attr(attr)
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{
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}
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template <typename Component>
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bool operator()(Component const& component)
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{
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// return true if the parser succeeds
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typedef typename Component::director director;
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typename
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traits::attribute_of<
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qi::domain, Component, Context, Iterator>::type
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val;
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if (director::parse(component, first, last, context, skipper, val))
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{
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attr = val;
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return true;
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}
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return false;
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}
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Iterator& first;
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Iterator const& last;
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Context& context;
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Skipper const& skipper;
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Attribute& attr;
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};
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template <typename Iterator, typename Context, typename Skipper>
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struct alternative_function<Iterator, Context, Skipper, unused_type const>
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{
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alternative_function(
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Iterator& first, Iterator const& last, Context& context,
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Skipper const& skipper, unused_type)
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: first(first), last(last), context(context), skipper(skipper)
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{
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}
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template <typename Component>
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bool operator()(Component const& component)
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{
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// return true if the parser succeeds
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typedef typename Component::director director;
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return director::parse(component, first, last, context, skipper,
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unused);
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}
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Iterator& first;
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Iterator const& last;
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Context& context;
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Skipper const& skipper;
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};
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}}}}
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#endif
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