1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/os/ossrv/ossrv_pub/boost_apis/boost/spirit/utility/confix.hpp Fri Jun 15 03:10:57 2012 +0200
1.3 @@ -0,0 +1,392 @@
1.4 +/*=============================================================================
1.5 + Copyright (c) 2002-2003 Hartmut Kaiser
1.6 + http://spirit.sourceforge.net/
1.7 +
1.8 + Use, modification and distribution is subject to the Boost Software
1.9 + License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
1.10 + http://www.boost.org/LICENSE_1_0.txt)
1.11 +=============================================================================*/
1.12 +#ifndef BOOST_SPIRIT_CONFIX_HPP
1.13 +#define BOOST_SPIRIT_CONFIX_HPP
1.14 +
1.15 +///////////////////////////////////////////////////////////////////////////////
1.16 +#include <boost/config.hpp>
1.17 +#include <boost/spirit/meta/as_parser.hpp>
1.18 +#include <boost/spirit/core/composite/operators.hpp>
1.19 +
1.20 +#include <boost/spirit/utility/confix_fwd.hpp>
1.21 +#include <boost/spirit/utility/impl/confix.ipp>
1.22 +
1.23 +///////////////////////////////////////////////////////////////////////////////
1.24 +namespace boost { namespace spirit {
1.25 +
1.26 +///////////////////////////////////////////////////////////////////////////////
1.27 +//
1.28 +// confix_parser class
1.29 +//
1.30 +// Parses a sequence of 3 sub-matches. This class may
1.31 +// be used to parse structures, where the opening part is possibly
1.32 +// contained in the expression part and the whole sequence is only
1.33 +// parsed after seeing the closing part matching the first opening
1.34 +// subsequence. Example: C-comments:
1.35 +//
1.36 +// /* This is a C-comment */
1.37 +//
1.38 +///////////////////////////////////////////////////////////////////////////////
1.39 +
1.40 +template<typename NestedT = non_nested, typename LexemeT = non_lexeme>
1.41 +struct confix_parser_gen;
1.42 +
1.43 +template <
1.44 + typename OpenT, typename ExprT, typename CloseT, typename CategoryT,
1.45 + typename NestedT, typename LexemeT
1.46 +>
1.47 +struct confix_parser :
1.48 + public parser<
1.49 + confix_parser<OpenT, ExprT, CloseT, CategoryT, NestedT, LexemeT>
1.50 + >
1.51 +{
1.52 + typedef
1.53 + confix_parser<OpenT, ExprT, CloseT, CategoryT, NestedT, LexemeT>
1.54 + self_t;
1.55 +
1.56 + confix_parser(OpenT const &open_, ExprT const &expr_, CloseT const &close_)
1.57 + : open(open_), expr(expr_), close(close_)
1.58 + {}
1.59 +
1.60 + template <typename ScannerT>
1.61 + typename parser_result<self_t, ScannerT>::type
1.62 + parse(ScannerT const& scan) const
1.63 + {
1.64 + return impl::confix_parser_type<CategoryT>::
1.65 + parse(NestedT(), LexemeT(), *this, scan, open, expr, close);
1.66 + }
1.67 +
1.68 +private:
1.69 +
1.70 + typename as_parser<OpenT>::type::embed_t open;
1.71 + typename as_parser<ExprT>::type::embed_t expr;
1.72 + typename as_parser<CloseT>::type::embed_t close;
1.73 +};
1.74 +
1.75 +///////////////////////////////////////////////////////////////////////////////
1.76 +//
1.77 +// Confix parser generator template
1.78 +//
1.79 +// This is a helper for generating a correct confix_parser<> from
1.80 +// auxiliary parameters. There are the following types supported as
1.81 +// parameters yet: parsers, single characters and strings (see
1.82 +// as_parser).
1.83 +//
1.84 +// If the body parser is an action_parser_category type parser (a parser
1.85 +// with an attached semantic action) we have to do something special. This
1.86 +// happens, if the user wrote something like:
1.87 +//
1.88 +// confix_p(open, body[f], close)
1.89 +//
1.90 +// where 'body' is the parser matching the body of the confix sequence
1.91 +// and 'f' is a functor to be called after matching the body. If we would
1.92 +// do nothing, the resulting code would parse the sequence as follows:
1.93 +//
1.94 +// start >> (body[f] - close) >> close
1.95 +//
1.96 +// what in most cases is not what the user expects.
1.97 +// (If this _is_ what you've expected, then please use the confix_p
1.98 +// generator function 'direct()', which will inhibit
1.99 +// re-attaching the actor to the body parser).
1.100 +//
1.101 +// To make the confix parser behave as expected:
1.102 +//
1.103 +// start >> (body - close)[f] >> close
1.104 +//
1.105 +// the actor attached to the 'body' parser has to be re-attached to the
1.106 +// (body - close) parser construct, which will make the resulting confix
1.107 +// parser 'do the right thing'. This refactoring is done by the help of
1.108 +// the refactoring parsers (see the files refactoring.[hi]pp).
1.109 +//
1.110 +// Additionally special care must be taken, if the body parser is a
1.111 +// unary_parser_category type parser as
1.112 +//
1.113 +// confix_p(open, *anychar_p, close)
1.114 +//
1.115 +// which without any refactoring would result in
1.116 +//
1.117 +// start >> (*anychar_p - close) >> close
1.118 +//
1.119 +// and will not give the expected result (*anychar_p will eat up all the
1.120 +// input up to the end of the input stream). So we have to refactor this
1.121 +// into:
1.122 +//
1.123 +// start >> *(anychar_p - close) >> close
1.124 +//
1.125 +// what will give the correct result.
1.126 +//
1.127 +// The case, where the body parser is a combination of the two mentioned
1.128 +// problems (i.e. the body parser is a unary parser with an attached
1.129 +// action), is handled accordingly too:
1.130 +//
1.131 +// confix_p(start, (*anychar_p)[f], end)
1.132 +//
1.133 +// will be parsed as expected:
1.134 +//
1.135 +// start >> (*(anychar_p - end))[f] >> end.
1.136 +//
1.137 +///////////////////////////////////////////////////////////////////////////////
1.138 +
1.139 +template<typename NestedT, typename LexemeT>
1.140 +struct confix_parser_gen
1.141 +{
1.142 + // Generic generator function for creation of concrete confix parsers
1.143 +
1.144 + template<typename StartT, typename ExprT, typename EndT>
1.145 + struct paren_op_result_type
1.146 + {
1.147 + typedef confix_parser<
1.148 + typename as_parser<StartT>::type,
1.149 + typename as_parser<ExprT>::type,
1.150 + typename as_parser<EndT>::type,
1.151 + typename as_parser<ExprT>::type::parser_category_t,
1.152 + NestedT,
1.153 + LexemeT
1.154 + > type;
1.155 + };
1.156 +
1.157 + template<typename StartT, typename ExprT, typename EndT>
1.158 + typename paren_op_result_type<StartT, ExprT, EndT>::type
1.159 + operator()(StartT const &start_, ExprT const &expr_, EndT const &end_) const
1.160 + {
1.161 + typedef typename paren_op_result_type<StartT,ExprT,EndT>::type
1.162 + return_t;
1.163 +
1.164 + return return_t(
1.165 + as_parser<StartT>::convert(start_),
1.166 + as_parser<ExprT>::convert(expr_),
1.167 + as_parser<EndT>::convert(end_)
1.168 + );
1.169 + }
1.170 +
1.171 + // Generic generator function for creation of concrete confix parsers
1.172 + // which have an action directly attached to the ExprT part of the
1.173 + // parser (see comment above, no automatic refactoring)
1.174 +
1.175 + template<typename StartT, typename ExprT, typename EndT>
1.176 + struct direct_result_type
1.177 + {
1.178 + typedef confix_parser<
1.179 + typename as_parser<StartT>::type,
1.180 + typename as_parser<ExprT>::type,
1.181 + typename as_parser<EndT>::type,
1.182 + plain_parser_category, // do not re-attach action
1.183 + NestedT,
1.184 + LexemeT
1.185 + > type;
1.186 + };
1.187 +
1.188 + template<typename StartT, typename ExprT, typename EndT>
1.189 + typename direct_result_type<StartT,ExprT,EndT>::type
1.190 + direct(StartT const &start_, ExprT const &expr_, EndT const &end_) const
1.191 + {
1.192 + typedef typename direct_result_type<StartT,ExprT,EndT>::type
1.193 + return_t;
1.194 +
1.195 + return return_t(
1.196 + as_parser<StartT>::convert(start_),
1.197 + as_parser<ExprT>::convert(expr_),
1.198 + as_parser<EndT>::convert(end_)
1.199 + );
1.200 + }
1.201 +};
1.202 +
1.203 +///////////////////////////////////////////////////////////////////////////////
1.204 +//
1.205 +// Predefined non_nested confix parser generators
1.206 +//
1.207 +///////////////////////////////////////////////////////////////////////////////
1.208 +
1.209 +const confix_parser_gen<non_nested, non_lexeme> confix_p =
1.210 + confix_parser_gen<non_nested, non_lexeme>();
1.211 +
1.212 +///////////////////////////////////////////////////////////////////////////////
1.213 +//
1.214 +// Comments are special types of confix parsers
1.215 +//
1.216 +// Comment parser generator template. This is a helper for generating a
1.217 +// correct confix_parser<> from auxiliary parameters, which is able to
1.218 +// parse comment constructs: (StartToken >> Comment text >> EndToken).
1.219 +//
1.220 +// There are the following types supported as parameters yet: parsers,
1.221 +// single characters and strings (see as_parser).
1.222 +//
1.223 +// There are two diffenerent predefined comment parser generators
1.224 +// (comment_p and comment_nest_p, see below), which may be used for
1.225 +// creating special comment parsers in two different ways.
1.226 +//
1.227 +// If these are used with one parameter, a comment starting with the given
1.228 +// first parser parameter up to the end of the line is matched. So for
1.229 +// instance the following parser matches C++ style comments:
1.230 +//
1.231 +// comment_p("//").
1.232 +//
1.233 +// If these are used with two parameters, a comment starting with the
1.234 +// first parser parameter up to the second parser parameter is matched.
1.235 +// For instance a C style comment parser should be constrcuted as:
1.236 +//
1.237 +// comment_p("/*", "*/").
1.238 +//
1.239 +// Please note, that a comment is parsed implicitly as if the whole
1.240 +// comment_p(...) statement were embedded into a lexeme_d[] directive.
1.241 +//
1.242 +///////////////////////////////////////////////////////////////////////////////
1.243 +
1.244 +template<typename NestedT>
1.245 +struct comment_parser_gen
1.246 +{
1.247 + // Generic generator function for creation of concrete comment parsers
1.248 + // from an open token. The newline parser eol_p is used as the
1.249 + // closing token.
1.250 +
1.251 + template<typename StartT>
1.252 + struct paren_op1_result_type
1.253 + {
1.254 + typedef confix_parser<
1.255 + typename as_parser<StartT>::type,
1.256 + kleene_star<anychar_parser>,
1.257 + alternative<eol_parser, end_parser>,
1.258 + unary_parser_category, // there is no action to re-attach
1.259 + NestedT,
1.260 + is_lexeme // insert implicit lexeme_d[]
1.261 + >
1.262 + type;
1.263 + };
1.264 +
1.265 + template<typename StartT>
1.266 + typename paren_op1_result_type<StartT>::type
1.267 + operator() (StartT const &start_) const
1.268 + {
1.269 + typedef typename paren_op1_result_type<StartT>::type
1.270 + return_t;
1.271 +
1.272 + return return_t(
1.273 + as_parser<StartT>::convert(start_),
1.274 + *anychar_p,
1.275 + eol_p | end_p
1.276 + );
1.277 + }
1.278 +
1.279 + // Generic generator function for creation of concrete comment parsers
1.280 + // from an open and a close tokens.
1.281 +
1.282 + template<typename StartT, typename EndT>
1.283 + struct paren_op2_result_type
1.284 + {
1.285 + typedef confix_parser<
1.286 + typename as_parser<StartT>::type,
1.287 + kleene_star<anychar_parser>,
1.288 + typename as_parser<EndT>::type,
1.289 + unary_parser_category, // there is no action to re-attach
1.290 + NestedT,
1.291 + is_lexeme // insert implicit lexeme_d[]
1.292 + > type;
1.293 + };
1.294 +
1.295 + template<typename StartT, typename EndT>
1.296 + typename paren_op2_result_type<StartT,EndT>::type
1.297 + operator() (StartT const &start_, EndT const &end_) const
1.298 + {
1.299 + typedef typename paren_op2_result_type<StartT,EndT>::type
1.300 + return_t;
1.301 +
1.302 + return return_t(
1.303 + as_parser<StartT>::convert(start_),
1.304 + *anychar_p,
1.305 + as_parser<EndT>::convert(end_)
1.306 + );
1.307 + }
1.308 +};
1.309 +
1.310 +///////////////////////////////////////////////////////////////////////////////
1.311 +//
1.312 +// Predefined non_nested comment parser generator
1.313 +//
1.314 +///////////////////////////////////////////////////////////////////////////////
1.315 +
1.316 +const comment_parser_gen<non_nested> comment_p =
1.317 + comment_parser_gen<non_nested>();
1.318 +
1.319 +///////////////////////////////////////////////////////////////////////////////
1.320 +//
1.321 +// comment_nest_parser class
1.322 +//
1.323 +// Parses a nested comments.
1.324 +// Example: nested PASCAL-comments:
1.325 +//
1.326 +// { This is a { nested } PASCAL-comment }
1.327 +//
1.328 +///////////////////////////////////////////////////////////////////////////////
1.329 +
1.330 +template<typename OpenT, typename CloseT>
1.331 +struct comment_nest_parser:
1.332 + public parser<comment_nest_parser<OpenT, CloseT> >
1.333 +{
1.334 + typedef comment_nest_parser<OpenT, CloseT> self_t;
1.335 +
1.336 + comment_nest_parser(OpenT const &open_, CloseT const &close_):
1.337 + open(open_), close(close_)
1.338 + {}
1.339 +
1.340 + template<typename ScannerT>
1.341 + typename parser_result<self_t, ScannerT>::type
1.342 + parse(ScannerT const &scan) const
1.343 + {
1.344 + return do_parse(
1.345 + open >> *(*this | (anychar_p - close)) >> close,
1.346 + scan);
1.347 + }
1.348 +
1.349 +private:
1.350 + template<typename ParserT, typename ScannerT>
1.351 + typename parser_result<self_t, ScannerT>::type
1.352 + do_parse(ParserT const &p, ScannerT const &scan) const
1.353 + {
1.354 + return
1.355 + impl::contiguous_parser_parse<
1.356 + typename parser_result<ParserT, ScannerT>::type
1.357 + >(p, scan, scan);
1.358 + }
1.359 +
1.360 + typename as_parser<OpenT>::type::embed_t open;
1.361 + typename as_parser<CloseT>::type::embed_t close;
1.362 +};
1.363 +
1.364 +///////////////////////////////////////////////////////////////////////////////
1.365 +//
1.366 +// Predefined nested comment parser generator
1.367 +//
1.368 +///////////////////////////////////////////////////////////////////////////////
1.369 +
1.370 +template<typename OpenT, typename CloseT>
1.371 +struct comment_nest_p_result
1.372 +{
1.373 + typedef comment_nest_parser<
1.374 + typename as_parser<OpenT>::type,
1.375 + typename as_parser<CloseT>::type
1.376 + > type;
1.377 +};
1.378 +
1.379 +template<typename OpenT, typename CloseT>
1.380 +inline typename comment_nest_p_result<OpenT,CloseT>::type
1.381 +comment_nest_p(OpenT const &open, CloseT const &close)
1.382 +{
1.383 + typedef typename comment_nest_p_result<OpenT,CloseT>::type
1.384 + result_t;
1.385 +
1.386 + return result_t(
1.387 + as_parser<OpenT>::convert(open),
1.388 + as_parser<CloseT>::convert(close)
1.389 + );
1.390 +}
1.391 +
1.392 +///////////////////////////////////////////////////////////////////////////////
1.393 +}} // namespace boost::spirit
1.394 +
1.395 +#endif