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-rw-r--r--3rdParty/Boost/src/boost/spirit/home/classic/core/composite/optional.hpp94
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diff --git a/3rdParty/Boost/src/boost/spirit/home/classic/core/composite/optional.hpp b/3rdParty/Boost/src/boost/spirit/home/classic/core/composite/optional.hpp
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+++ b/3rdParty/Boost/src/boost/spirit/home/classic/core/composite/optional.hpp
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+/*=============================================================================
+ Copyright (c) 1998-2003 Joel de Guzman
+ Copyright (c) 2001 Daniel Nuffer
+ Copyright (c) 2002 Hartmut Kaiser
+ http://spirit.sourceforge.net/
+
+ 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_OPTIONAL_HPP)
+#define BOOST_SPIRIT_OPTIONAL_HPP
+
+#include <boost/spirit/home/classic/namespace.hpp>
+#include <boost/spirit/home/classic/core/parser.hpp>
+#include <boost/spirit/home/classic/core/primitives/primitives.hpp>
+#include <boost/spirit/home/classic/core/composite/composite.hpp>
+#include <boost/spirit/home/classic/meta/as_parser.hpp>
+
+namespace boost { namespace spirit {
+
+BOOST_SPIRIT_CLASSIC_NAMESPACE_BEGIN
+
+ ///////////////////////////////////////////////////////////////////////////
+ //
+ // optional class
+ //
+ // Handles expressions of the form:
+ //
+ // !a
+ //
+ // where a is a parser. The expression returns a composite
+ // parser that matches its subject zero (0) or one (1) time.
+ //
+ ///////////////////////////////////////////////////////////////////////////
+ struct optional_parser_gen;
+
+ template <typename S>
+ struct optional
+ : public unary<S, parser<optional<S> > >
+ {
+ typedef optional<S> self_t;
+ typedef unary_parser_category parser_category_t;
+ typedef optional_parser_gen parser_generator_t;
+ typedef unary<S, parser<self_t> > base_t;
+
+ optional(S const& a)
+ : base_t(a) {}
+
+ template <typename ScannerT>
+ typename parser_result<self_t, ScannerT>::type
+ parse(ScannerT const& scan) const
+ {
+ typedef typename parser_result<self_t, ScannerT>::type result_t;
+ typedef typename ScannerT::iterator_t iterator_t;
+ iterator_t save = scan.first;
+ if (result_t r = this->subject().parse(scan))
+ {
+ return r;
+ }
+ else
+ {
+ scan.first = save;
+ return scan.empty_match();
+ }
+ }
+ };
+
+ struct optional_parser_gen
+ {
+ template <typename S>
+ struct result
+ {
+ typedef optional<S> type;
+ };
+
+ template <typename S>
+ static optional<S>
+ generate(parser<S> const& a)
+ {
+ return optional<S>(a.derived());
+ }
+ };
+
+ template <typename S>
+ optional<S>
+ operator!(parser<S> const& a);
+
+BOOST_SPIRIT_CLASSIC_NAMESPACE_END
+
+}} // namespace BOOST_SPIRIT_CLASSIC_NS
+
+#endif
+
+#include <boost/spirit/home/classic/core/composite/impl/optional.ipp>