ceph/src/boost/libs/spirit/example/qi/compiler_tutorial/calc8/statement_def.hpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2011 Joel de Guzman
   3
   4     Distributed under the Boost Software License, Version 1.0. (See accompanying
   5     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 =============================================================================*/
   7 #include "statement.hpp"
   8 #include "error_handler.hpp"
   9 #include "annotation.hpp"
  10
  11 namespace client { namespace parser
  12 {
  13     template <typename Iterator>
  14     statement<Iterator>::statement(error_handler<Iterator>& error_handler)
  15       : statement::base_type(statement_list), expr(error_handler)
  16     {
  17         qi::_1_type _1;
  18         qi::_2_type _2;
  19         qi::_3_type _3;
  20         qi::_4_type _4;
  21
  22         qi::_val_type _val;
  23         qi::raw_type raw;
  24         qi::lexeme_type lexeme;
  25         qi::alpha_type alpha;
  26         qi::alnum_type alnum;
  27         qi::lit_type lit;
  28
  29         using qi::on_error;
  30         using qi::on_success;
  31         using qi::fail;
  32         using boost::phoenix::function;
  33
  34         typedef function<client::error_handler<Iterator> > error_handler_function;
  35         typedef function<client::annotation<Iterator> > annotation_function;
  36
  37         statement_list =
  38             +statement_
  39             ;
  40
  41         statement_ =
  42                 variable_declaration
  43             |   assignment
  44             |   compound_statement
  45             |   if_statement
  46             |   while_statement
  47             ;
  48
  49         identifier =
  50                 !expr.keywords
  51             >>  raw[lexeme[(alpha | '_') >> *(alnum | '_')]]
  52             ;
  53
  54         variable_declaration =
  55                 lexeme["var" >> !(alnum | '_')] // make sure we have whole words
  56             >   &identifier // expect an identifier
  57             >   assignment
  58             ;
  59
  60         assignment =
  61                 identifier
  62             >   '='
  63             >   expr
  64             >   ';'
  65             ;
  66
  67         if_statement =
  68                 lit("if")
  69             >   '('
  70             >   expr
  71             >   ')'
  72             >   statement_
  73             >
  74                -(
  75                     lexeme["else" >> !(alnum | '_')] // make sure we have whole words
  76                 >   statement_
  77                 )
  78             ;
  79
  80         while_statement =
  81                 lit("while")
  82             >   '('
  83             >   expr
  84             >   ')'
  85             >   statement_
  86             ;
  87
  88         compound_statement =
  89             '{' >> -statement_list >> '}'
  90             ;
  91
  92         // Debugging and error handling and reporting support.
  93         BOOST_SPIRIT_DEBUG_NODES(
  94             (statement_list)
  95             (identifier)
  96             (variable_declaration)
  97             (assignment)
  98         );
  99
 100         // Error handling: on error in statement_list, call error_handler.
 101         on_error<fail>(statement_list,
 102             error_handler_function(error_handler)(
 103                 "Error! Expecting ", _4, _3));
 104
 105         // Annotation: on success in assignment, call annotation.
 106         on_success(assignment,
 107             annotation_function(error_handler.iters)(_val, _1));
 108     }
 109 }}
 110
 111