libs/spirit/example/qi/compiler_tutorial/calc8/expression_def.hpp

/*=============================================================================
    Copyright (c) 2001-2011 Joel de Guzman

    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)
=============================================================================*/
#include "expression.hpp"
#include "error_handler.hpp"
#include "annotation.hpp"
#include <boost/spirit/include/phoenix_function.hpp>

namespace client { namespace parser
{
    template <typename Iterator>
    expression<Iterator>::expression(error_handler<Iterator>& error_handler)
      : expression::base_type(expr)
    {
        qi::_1_type _1;
        qi::_2_type _2;
        qi::_3_type _3;
        qi::_4_type _4;

        qi::char_type char_;
        qi::uint_type uint_;
        qi::_val_type _val;
        qi::raw_type raw;
        qi::lexeme_type lexeme;
        qi::alpha_type alpha;
        qi::alnum_type alnum;
        qi::bool_type bool_;

        using qi::on_error;
        using qi::on_success;
        using qi::fail;
        using boost::phoenix::function;

        typedef function<client::error_handler<Iterator> > error_handler_function;
        typedef function<client::annotation<Iterator> > annotation_function;

        ///////////////////////////////////////////////////////////////////////
        // Tokens
        equality_op.add
            ("==", ast::op_equal)
            ("!=", ast::op_not_equal)
            ;

        relational_op.add
            ("<", ast::op_less)
            ("<=", ast::op_less_equal)
            (">", ast::op_greater)
            (">=", ast::op_greater_equal)
            ;

        logical_op.add
            ("&&", ast::op_and)
            ("||", ast::op_or)
            ;

        additive_op.add
            ("+", ast::op_plus)
            ("-", ast::op_minus)
            ;

        multiplicative_op.add
            ("*", ast::op_times)
            ("/", ast::op_divide)
            ;

        unary_op.add
            ("+", ast::op_positive)
            ("-", ast::op_negative)
            ("!", ast::op_not)
            ;

        keywords.add
            ("var")
            ("true")
            ("false")
            ("if")
            ("else")
            ("while")
            ;

        ///////////////////////////////////////////////////////////////////////
        // Main expression grammar
        expr =
            equality_expr.alias()
            ;

        equality_expr =
                relational_expr
            >> *(equality_op > relational_expr)
            ;

        relational_expr =
                logical_expr
            >> *(relational_op > logical_expr)
            ;

        logical_expr =
                additive_expr
            >> *(logical_op > additive_expr)
            ;

        additive_expr =
                multiplicative_expr
            >> *(additive_op > multiplicative_expr)
            ;

        multiplicative_expr =
                unary_expr
            >> *(multiplicative_op > unary_expr)
            ;

        unary_expr =
                primary_expr
            |   (unary_op > primary_expr)
            ;

        primary_expr =
                uint_
            |   identifier
            |   bool_
            |   '(' > expr > ')'
            ;

        identifier =
                !keywords
            >>  raw[lexeme[(alpha | '_') >> *(alnum | '_')]]
            ;

        ///////////////////////////////////////////////////////////////////////
        // Debugging and error handling and reporting support.
        BOOST_SPIRIT_DEBUG_NODES(
            (expr)
            (equality_expr)
            (relational_expr)
            (logical_expr)
            (additive_expr)
            (multiplicative_expr)
            (unary_expr)
            (primary_expr)
            (identifier)
        );

        ///////////////////////////////////////////////////////////////////////
        // Error handling: on error in expr, call error_handler.
        on_error<fail>(expr,
            error_handler_function(error_handler)(
                "Error! Expecting ", _4, _3));

        ///////////////////////////////////////////////////////////////////////
        // Annotation: on success in primary_expr, call annotation.
        on_success(primary_expr,
            annotation_function(error_handler.iters)(_val, _1));
    }
}}