[857] | 1 | /*=============================================================================
|
---|
| 2 | Copyright (c) 2002-2003 Hartmut Kaiser
|
---|
| 3 | http://spirit.sourceforge.net/
|
---|
| 4 |
|
---|
| 5 | Use, modification and distribution is subject to the Boost Software
|
---|
| 6 | License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
|
---|
| 7 | http://www.boost.org/LICENSE_1_0.txt)
|
---|
| 8 | =============================================================================*/
|
---|
| 9 | #ifndef BOOST_SPIRIT_LISTS_HPP
|
---|
| 10 | #define BOOST_SPIRIT_LISTS_HPP
|
---|
| 11 |
|
---|
| 12 | ///////////////////////////////////////////////////////////////////////////////
|
---|
| 13 | #include <boost/config.hpp>
|
---|
| 14 | #include <boost/spirit/meta/as_parser.hpp>
|
---|
| 15 | #include <boost/spirit/core/parser.hpp>
|
---|
| 16 | #include <boost/spirit/core/composite/composite.hpp>
|
---|
| 17 | #include <boost/spirit/utility/impl/lists.ipp>
|
---|
| 18 |
|
---|
| 19 | ///////////////////////////////////////////////////////////////////////////////
|
---|
| 20 | namespace boost { namespace spirit {
|
---|
| 21 |
|
---|
| 22 | ///////////////////////////////////////////////////////////////////////////////
|
---|
| 23 | //
|
---|
| 24 | // list_parser class
|
---|
| 25 | //
|
---|
| 26 | // List parsers allow to parse constructs like
|
---|
| 27 | //
|
---|
| 28 | // item >> *(delim >> item)
|
---|
| 29 | //
|
---|
| 30 | // where 'item' is an auxiliary expression to parse and 'delim' is an
|
---|
| 31 | // auxiliary delimiter to parse.
|
---|
| 32 | //
|
---|
| 33 | // The list_parser class also can match an optional closing delimiter
|
---|
| 34 | // represented by the 'end' parser at the end of the list:
|
---|
| 35 | //
|
---|
| 36 | // item >> *(delim >> item) >> !end.
|
---|
| 37 | //
|
---|
| 38 | // If ItemT is an action_parser_category type (parser with an attached
|
---|
| 39 | // semantic action) we have to do something special. This happens, if the
|
---|
| 40 | // user wrote something like:
|
---|
| 41 | //
|
---|
| 42 | // list_p(item[f], delim)
|
---|
| 43 | //
|
---|
| 44 | // where 'item' is the parser matching one item of the list sequence and
|
---|
| 45 | // 'f' is a functor to be called after matching one item. If we would do
|
---|
| 46 | // nothing, the resulting code would parse the sequence as follows:
|
---|
| 47 | //
|
---|
| 48 | // (item[f] - delim) >> *(delim >> (item[f] - delim))
|
---|
| 49 | //
|
---|
| 50 | // what in most cases is not what the user expects.
|
---|
| 51 | // (If this _is_ what you've expected, then please use one of the list_p
|
---|
| 52 | // generator functions 'direct()', which will inhibit re-attaching
|
---|
| 53 | // the actor to the item parser).
|
---|
| 54 | //
|
---|
| 55 | // To make the list parser behave as expected:
|
---|
| 56 | //
|
---|
| 57 | // (item - delim)[f] >> *(delim >> (item - delim)[f])
|
---|
| 58 | //
|
---|
| 59 | // the actor attached to the 'item' parser has to be re-attached to the
|
---|
| 60 | // *(item - delim) parser construct, which will make the resulting list
|
---|
| 61 | // parser 'do the right thing'.
|
---|
| 62 | //
|
---|
| 63 | // Additionally special care must be taken, if the item parser is a
|
---|
| 64 | // unary_parser_category type parser as
|
---|
| 65 | //
|
---|
| 66 | // list_p(*anychar_p, ',')
|
---|
| 67 | //
|
---|
| 68 | // which without any refactoring would result in
|
---|
| 69 | //
|
---|
| 70 | // (*anychar_p - ch_p(','))
|
---|
| 71 | // >> *( ch_p(',') >> (*anychar_p - ch_p(',')) )
|
---|
| 72 | //
|
---|
| 73 | // and will not give the expected result (the first *anychar_p will eat up
|
---|
| 74 | // all the input up to the end of the input stream). So we have to
|
---|
| 75 | // refactor this into:
|
---|
| 76 | //
|
---|
| 77 | // *(anychar_p - ch_p(','))
|
---|
| 78 | // >> *( ch_p(',') >> *(anychar_p - ch_p(',')) )
|
---|
| 79 | //
|
---|
| 80 | // what will give the correct result.
|
---|
| 81 | //
|
---|
| 82 | // The case, where the item parser is a combination of the two mentioned
|
---|
| 83 | // problems (i.e. the item parser is a unary parser with an attached
|
---|
| 84 | // action), is handled accordingly too:
|
---|
| 85 | //
|
---|
| 86 | // list_p((*anychar_p)[f], ',')
|
---|
| 87 | //
|
---|
| 88 | // will be parsed as expected:
|
---|
| 89 | //
|
---|
| 90 | // (*(anychar_p - ch_p(',')))[f]
|
---|
| 91 | // >> *( ch_p(',') >> (*(anychar_p - ch_p(',')))[f] ).
|
---|
| 92 | //
|
---|
| 93 | ///////////////////////////////////////////////////////////////////////////////
|
---|
| 94 | template <
|
---|
| 95 | typename ItemT, typename DelimT, typename EndT = no_list_endtoken,
|
---|
| 96 | typename CategoryT = plain_parser_category
|
---|
| 97 | >
|
---|
| 98 | struct list_parser :
|
---|
| 99 | public parser<list_parser<ItemT, DelimT, EndT, CategoryT> > {
|
---|
| 100 |
|
---|
| 101 | typedef list_parser<ItemT, DelimT, EndT, CategoryT> self_t;
|
---|
| 102 | typedef CategoryT parser_category_t;
|
---|
| 103 |
|
---|
| 104 | list_parser(ItemT const &item_, DelimT const &delim_,
|
---|
| 105 | EndT const& end_ = no_list_endtoken())
|
---|
| 106 | : item(item_), delim(delim_), end(end_)
|
---|
| 107 | {}
|
---|
| 108 |
|
---|
| 109 | template <typename ScannerT>
|
---|
| 110 | typename parser_result<self_t, ScannerT>::type
|
---|
| 111 | parse(ScannerT const& scan) const
|
---|
| 112 | {
|
---|
| 113 | return impl::list_parser_type<CategoryT>
|
---|
| 114 | ::parse(scan, *this, item, delim, end);
|
---|
| 115 | }
|
---|
| 116 |
|
---|
| 117 | private:
|
---|
| 118 | typename as_parser<ItemT>::type::embed_t item;
|
---|
| 119 | typename as_parser<DelimT>::type::embed_t delim;
|
---|
| 120 | typename as_parser<EndT>::type::embed_t end;
|
---|
| 121 | };
|
---|
| 122 |
|
---|
| 123 | ///////////////////////////////////////////////////////////////////////////////
|
---|
| 124 | //
|
---|
| 125 | // List parser generator template
|
---|
| 126 | //
|
---|
| 127 | // This is a helper for generating a correct list_parser<> from
|
---|
| 128 | // auxiliary parameters. There are the following types supported as
|
---|
| 129 | // parameters yet: parsers, single characters and strings (see
|
---|
| 130 | // as_parser<> in meta/as_parser.hpp).
|
---|
| 131 | //
|
---|
| 132 | // The list_parser_gen by itself can be used for parsing comma separated
|
---|
| 133 | // lists without item formatting:
|
---|
| 134 | //
|
---|
| 135 | // list_p.parse(...)
|
---|
| 136 | // matches any comma separated list.
|
---|
| 137 | //
|
---|
| 138 | // If list_p is used with one parameter, this parameter is used to match
|
---|
| 139 | // the delimiter:
|
---|
| 140 | //
|
---|
| 141 | // list_p(';').parse(...)
|
---|
| 142 | // matches any semicolon separated list.
|
---|
| 143 | //
|
---|
| 144 | // If list_p is used with two parameters, the first parameter is used to
|
---|
| 145 | // match the items and the second parameter matches the delimiters:
|
---|
| 146 | //
|
---|
| 147 | // list_p(uint_p, ',').parse(...)
|
---|
| 148 | // matches comma separated unsigned integers.
|
---|
| 149 | //
|
---|
| 150 | // If list_p is used with three parameters, the first parameter is used
|
---|
| 151 | // to match the items, the second one is used to match the delimiters and
|
---|
| 152 | // the third one is used to match an optional ending token sequence:
|
---|
| 153 | //
|
---|
| 154 | // list_p(real_p, ';', eol_p).parse(...)
|
---|
| 155 | // matches a semicolon separated list of real numbers optionally
|
---|
| 156 | // followed by an end of line.
|
---|
| 157 | //
|
---|
| 158 | // The list_p in the previous examples denotes the predefined parser
|
---|
| 159 | // generator, which should be used to define list parsers (see below).
|
---|
| 160 | //
|
---|
| 161 | ///////////////////////////////////////////////////////////////////////////////
|
---|
| 162 |
|
---|
| 163 | template <typename CharT = char>
|
---|
| 164 | struct list_parser_gen :
|
---|
| 165 | public list_parser<kleene_star<anychar_parser>, chlit<CharT> >
|
---|
| 166 | {
|
---|
| 167 | typedef list_parser_gen<CharT> self_t;
|
---|
| 168 |
|
---|
| 169 | // construct the list_parser_gen object as an list parser for comma separated
|
---|
| 170 | // lists without item formatting.
|
---|
| 171 | list_parser_gen()
|
---|
| 172 | : list_parser<kleene_star<anychar_parser>, chlit<CharT> >
|
---|
| 173 | (*anychar_p, chlit<CharT>(','))
|
---|
| 174 | {}
|
---|
| 175 |
|
---|
| 176 | // The following generator functions should be used under normal circumstances.
|
---|
| 177 | // (the operator()(...) functions)
|
---|
| 178 |
|
---|
| 179 | // Generic generator functions for creation of concrete list parsers, which
|
---|
| 180 | // support 'normal' syntax:
|
---|
| 181 | //
|
---|
| 182 | // item >> *(delim >> item)
|
---|
| 183 | //
|
---|
| 184 | // If item isn't given, everything between two delimiters is matched.
|
---|
| 185 |
|
---|
| 186 | template<typename DelimT>
|
---|
| 187 | list_parser<
|
---|
| 188 | kleene_star<anychar_parser>,
|
---|
| 189 | typename as_parser<DelimT>::type,
|
---|
| 190 | no_list_endtoken,
|
---|
| 191 | unary_parser_category // there is no action to re-attach
|
---|
| 192 | >
|
---|
| 193 | operator()(DelimT const &delim_) const
|
---|
| 194 | {
|
---|
| 195 | typedef kleene_star<anychar_parser> item_t;
|
---|
| 196 | typedef typename as_parser<DelimT>::type delim_t;
|
---|
| 197 |
|
---|
| 198 | typedef
|
---|
| 199 | list_parser<item_t, delim_t, no_list_endtoken, unary_parser_category>
|
---|
| 200 | return_t;
|
---|
| 201 |
|
---|
| 202 | return return_t(*anychar_p, as_parser<DelimT>::convert(delim_));
|
---|
| 203 | }
|
---|
| 204 |
|
---|
| 205 | template<typename ItemT, typename DelimT>
|
---|
| 206 | list_parser<
|
---|
| 207 | typename as_parser<ItemT>::type,
|
---|
| 208 | typename as_parser<DelimT>::type,
|
---|
| 209 | no_list_endtoken,
|
---|
| 210 | typename as_parser<ItemT>::type::parser_category_t
|
---|
| 211 | >
|
---|
| 212 | operator()(ItemT const &item_, DelimT const &delim_) const
|
---|
| 213 | {
|
---|
| 214 | typedef typename as_parser<ItemT>::type item_t;
|
---|
| 215 | typedef typename as_parser<DelimT>::type delim_t;
|
---|
| 216 | typedef list_parser<item_t, delim_t, no_list_endtoken,
|
---|
| 217 | BOOST_DEDUCED_TYPENAME item_t::parser_category_t>
|
---|
| 218 | return_t;
|
---|
| 219 |
|
---|
| 220 | return return_t(
|
---|
| 221 | as_parser<ItemT>::convert(item_),
|
---|
| 222 | as_parser<DelimT>::convert(delim_)
|
---|
| 223 | );
|
---|
| 224 | }
|
---|
| 225 |
|
---|
| 226 | // Generic generator function for creation of concrete list parsers, which
|
---|
| 227 | // support 'extended' syntax:
|
---|
| 228 | //
|
---|
| 229 | // item >> *(delim >> item) >> !end
|
---|
| 230 |
|
---|
| 231 | template<typename ItemT, typename DelimT, typename EndT>
|
---|
| 232 | list_parser<
|
---|
| 233 | typename as_parser<ItemT>::type,
|
---|
| 234 | typename as_parser<DelimT>::type,
|
---|
| 235 | typename as_parser<EndT>::type,
|
---|
| 236 | typename as_parser<ItemT>::type::parser_category_t
|
---|
| 237 | >
|
---|
| 238 | operator()(
|
---|
| 239 | ItemT const &item_, DelimT const &delim_, EndT const &end_) const
|
---|
| 240 | {
|
---|
| 241 | typedef typename as_parser<ItemT>::type item_t;
|
---|
| 242 | typedef typename as_parser<DelimT>::type delim_t;
|
---|
| 243 | typedef typename as_parser<EndT>::type end_t;
|
---|
| 244 |
|
---|
| 245 | typedef list_parser<item_t, delim_t, end_t,
|
---|
| 246 | BOOST_DEDUCED_TYPENAME item_t::parser_category_t>
|
---|
| 247 | return_t;
|
---|
| 248 |
|
---|
| 249 | return return_t(
|
---|
| 250 | as_parser<ItemT>::convert(item_),
|
---|
| 251 | as_parser<DelimT>::convert(delim_),
|
---|
| 252 | as_parser<EndT>::convert(end_)
|
---|
| 253 | );
|
---|
| 254 | }
|
---|
| 255 |
|
---|
| 256 | // The following functions should be used, if the 'item' parser has an attached
|
---|
| 257 | // semantic action or is a unary_parser_category type parser and the structure
|
---|
| 258 | // of the resulting list parser should _not_ be refactored during parser
|
---|
| 259 | // construction (see comment above).
|
---|
| 260 |
|
---|
| 261 | // Generic generator function for creation of concrete list parsers, which
|
---|
| 262 | // support 'normal' syntax:
|
---|
| 263 | //
|
---|
| 264 | // item >> *(delim >> item)
|
---|
| 265 |
|
---|
| 266 | template<typename ItemT, typename DelimT>
|
---|
| 267 | list_parser<
|
---|
| 268 | typename as_parser<ItemT>::type,
|
---|
| 269 | typename as_parser<DelimT>::type,
|
---|
| 270 | no_list_endtoken,
|
---|
| 271 | plain_parser_category // inhibit action re-attachment
|
---|
| 272 | >
|
---|
| 273 | direct(ItemT const &item_, DelimT const &delim_) const
|
---|
| 274 | {
|
---|
| 275 | typedef typename as_parser<ItemT>::type item_t;
|
---|
| 276 | typedef typename as_parser<DelimT>::type delim_t;
|
---|
| 277 | typedef list_parser<item_t, delim_t, no_list_endtoken,
|
---|
| 278 | plain_parser_category>
|
---|
| 279 | return_t;
|
---|
| 280 |
|
---|
| 281 | return return_t(
|
---|
| 282 | as_parser<ItemT>::convert(item_),
|
---|
| 283 | as_parser<DelimT>::convert(delim_)
|
---|
| 284 | );
|
---|
| 285 | }
|
---|
| 286 |
|
---|
| 287 | // Generic generator function for creation of concrete list parsers, which
|
---|
| 288 | // support 'extended' syntax:
|
---|
| 289 | //
|
---|
| 290 | // item >> *(delim >> item) >> !end
|
---|
| 291 |
|
---|
| 292 | template<typename ItemT, typename DelimT, typename EndT>
|
---|
| 293 | list_parser<
|
---|
| 294 | typename as_parser<ItemT>::type,
|
---|
| 295 | typename as_parser<DelimT>::type,
|
---|
| 296 | typename as_parser<EndT>::type,
|
---|
| 297 | plain_parser_category // inhibit action re-attachment
|
---|
| 298 | >
|
---|
| 299 | direct(
|
---|
| 300 | ItemT const &item_, DelimT const &delim_, EndT const &end_) const
|
---|
| 301 | {
|
---|
| 302 | typedef typename as_parser<ItemT>::type item_t;
|
---|
| 303 | typedef typename as_parser<DelimT>::type delim_t;
|
---|
| 304 | typedef typename as_parser<EndT>::type end_t;
|
---|
| 305 |
|
---|
| 306 | typedef
|
---|
| 307 | list_parser<item_t, delim_t, end_t, plain_parser_category>
|
---|
| 308 | return_t;
|
---|
| 309 |
|
---|
| 310 | return return_t(
|
---|
| 311 | as_parser<ItemT>::convert(item_),
|
---|
| 312 | as_parser<DelimT>::convert(delim_),
|
---|
| 313 | as_parser<EndT>::convert(end_)
|
---|
| 314 | );
|
---|
| 315 | }
|
---|
| 316 | };
|
---|
| 317 |
|
---|
| 318 | ///////////////////////////////////////////////////////////////////////////////
|
---|
| 319 | //
|
---|
| 320 | // Predefined list parser generator
|
---|
| 321 | //
|
---|
| 322 | // The list_p parser generator can be used
|
---|
| 323 | // - by itself for parsing comma separated lists without item formatting
|
---|
| 324 | // or
|
---|
| 325 | // - for generating list parsers with auxiliary parser parameters
|
---|
| 326 | // for the 'item', 'delim' and 'end' subsequences.
|
---|
| 327 | // (see comment above)
|
---|
| 328 | //
|
---|
| 329 | ///////////////////////////////////////////////////////////////////////////////
|
---|
| 330 | const list_parser_gen<> list_p = list_parser_gen<>();
|
---|
| 331 |
|
---|
| 332 | ///////////////////////////////////////////////////////////////////////////////
|
---|
| 333 | }} // namespace boost::spirit
|
---|
| 334 |
|
---|
| 335 | #endif
|
---|