Project Description

The Hime Parser Generator generates lexers and parsers for .Net 2.0 and above. It supports deterministic (LALR) and generalized (GLR) parsing methods.

Features

  • Generate lexers and parsers either through the command line tool or programmatically using the library.
  • Generate either the lexers and parsers as C# sources, or the compiled version as a .Net assembly.
  • Generate a documentation of the produced parsers for debugging purposes as HTML pages.
  • Expressive input language for the specification of lexical and syntactical rules.

Quick How-to

Write your grammar in the input language. For example, a grammar for simple mathematical expressions:
cf grammar MathExp
{
    options
    {
        Axiom = "exp";
        Separator = "SEPARATOR";
    }
    terminals {
        INTEGER    -> [1-9] [0-9]* | '0' ;
        REAL        -> INTEGER? '.' INTEGER  (('e' | 'E') ('+' | '-')? INTEGER)?
                    |  INTEGER ('e' | 'E') ('+' | '-')? INTEGER ;
        NUMBER    -> INTEGER | REAL ;
        WHITE_SPACE    -> 0x0020 | 0x0009 | 0x000B | 0x000C ;
        SEPARATOR    -> WHITE_SPACE+;
    }
    rules {
        exp_atom-> NUMBER
            | '(' exp ')' ;
        exp_op0    -> exp_atom
            |  exp_op0 '*' exp_atom
            |  exp_op0 '/' exp_atom;
        exp_op1    -> exp_op0
            |  exp_op1 '+' exp_op0 
            |  exp_op1 '-' exp_op0;
        exp    -> exp_op1 ;
    }
}


Execute the following command line:
himecc MathExp.gram

The program generates 4 files:
  • MathExpLexer.cs, a C# source file for the generated lexer to be included in your project
  • MathExpParser.cs, a C# source file for the generated parser to be included in your project
  • MathExpLexer.bin, a resource file to be included as an embedded resource in your project
  • MathExpParser.bin, a resource file to be included as an embedded resource in your project

To parse mathematical expression, include a reference to Hime.Redist.dll in your project and use the following lines:
MathExpLexer lexer = new MathExpLexer("2 + 3");
MathExpParser parser = new MathExpParser(lexer);
ASTNode root = parser.Parse() ;

Last edited May 14 at 9:59 AM by lwouters, version 14