ceph/src/boost/libs/spirit/example/qi/compiler_tutorial/calc8/ast.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 #if !defined(BOOST_SPIRIT_CALC8_AST_HPP)
   8 #define BOOST_SPIRIT_CALC8_AST_HPP
   9
  10 #include <boost/variant/recursive_variant.hpp>
  11 #include <boost/fusion/include/adapt_struct.hpp>
  12 #include <boost/fusion/include/io.hpp>
  13 #include <boost/optional.hpp>
  14 #include <list>
  15
  16 namespace client { namespace ast
  17 {
  18     ///////////////////////////////////////////////////////////////////////////
  19     //  The AST
  20     ///////////////////////////////////////////////////////////////////////////
  21     struct tagged
  22     {
  23         int id; // Used to annotate the AST with the iterator position.
  24                 // This id is used as a key to a map<int, Iterator>
  25                 // (not really part of the AST.)
  26     };
  27
  28     struct nil {};
  29     struct unary;
  30     struct expression;
  31
  32     struct variable : tagged
  33     {
  34         variable(std::string const& name = "") : name(name) {}
  35         std::string name;
  36     };
  37
  38     typedef boost::variant<
  39             nil
  40           , bool
  41           , unsigned int
  42           , variable
  43           , boost::recursive_wrapper<unary>
  44           , boost::recursive_wrapper<expression>
  45         >
  46     operand;
  47
  48     enum optoken
  49     {
  50         op_plus,
  51         op_minus,
  52         op_times,
  53         op_divide,
  54         op_positive,
  55         op_negative,
  56         op_not,
  57         op_equal,
  58         op_not_equal,
  59         op_less,
  60         op_less_equal,
  61         op_greater,
  62         op_greater_equal,
  63         op_and,
  64         op_or
  65     };
  66
  67     struct unary
  68     {
  69         optoken operator_;
  70         operand operand_;
  71     };
  72
  73     struct operation
  74     {
  75         optoken operator_;
  76         operand operand_;
  77     };
  78
  79     struct expression
  80     {
  81         operand first;
  82         std::list<operation> rest;
  83     };
  84
  85     struct assignment
  86     {
  87         variable lhs;
  88         expression rhs;
  89     };
  90
  91     struct variable_declaration
  92     {
  93         assignment assign;
  94     };
  95
  96     struct if_statement;
  97     struct while_statement;
  98     struct statement_list;
  99
 100     typedef boost::variant<
 101             variable_declaration
 102           , assignment
 103           , boost::recursive_wrapper<if_statement>
 104           , boost::recursive_wrapper<while_statement>
 105           , boost::recursive_wrapper<statement_list>
 106         >
 107     statement;
 108
 109     struct statement_list : std::list<statement> {};
 110
 111     struct if_statement
 112     {
 113         expression condition;
 114         statement then;
 115         boost::optional<statement> else_;
 116     };
 117
 118     struct while_statement
 119     {
 120         expression condition;
 121         statement body;
 122     };
 123
 124     // print functions for debugging
 125     inline std::ostream& operator<<(std::ostream& out, nil) { out << "nil"; return out; }
 126     inline std::ostream& operator<<(std::ostream& out, variable const& var) { out << var.name; return out; }
 127 }}
 128
 129 BOOST_FUSION_ADAPT_STRUCT(
 130     client::ast::unary,
 131     (client::ast::optoken, operator_)
 132     (client::ast::operand, operand_)
 133 )
 134
 135 BOOST_FUSION_ADAPT_STRUCT(
 136     client::ast::operation,
 137     (client::ast::optoken, operator_)
 138     (client::ast::operand, operand_)
 139 )
 140
 141 BOOST_FUSION_ADAPT_STRUCT(
 142     client::ast::expression,
 143     (client::ast::operand, first)
 144     (std::list<client::ast::operation>, rest)
 145 )
 146
 147 BOOST_FUSION_ADAPT_STRUCT(
 148     client::ast::variable_declaration,
 149     (client::ast::assignment, assign)
 150 )
 151
 152 BOOST_FUSION_ADAPT_STRUCT(
 153     client::ast::assignment,
 154     (client::ast::variable, lhs)
 155     (client::ast::expression, rhs)
 156 )
 157
 158 BOOST_FUSION_ADAPT_STRUCT(
 159     client::ast::if_statement,
 160     (client::ast::expression, condition)
 161     (client::ast::statement, then)
 162     (boost::optional<client::ast::statement>, else_)
 163 )
 164
 165 BOOST_FUSION_ADAPT_STRUCT(
 166     client::ast::while_statement,
 167     (client::ast::expression, condition)
 168     (client::ast::statement, body)
 169 )
 170
 171 #endif