Notes and documentation
last updated 2008 Mar 17

About Augmented Syntax Diagrams

• Augmented Syntax Diagrams - a brief description of ASD grammars and how they compare with Augmented Transition Network (ATN) grammars.
• Although Augmented Syntax Diagrams are designed to represent grammars of natural languages, which are generally ambiguous syntactically, ASDs can also represent grammars of programming languages and other artifical languages.  An example is provided by a grammar for arithmetic expressions and an evaluator that uses the grammar.  The application can be run as a Java applet by clicking on this link: Evaluator.  (The applet was created by Roxanne Parent.  Note: The Evaluator applet window must be closed by using the Action Exit menu option, not by clicking on the button in the upper right-hand corner of the window.)  When ASDParser is used with an unambiguous grammar like that of arithmetic expressions or of a programming language, it can parse expressions in those languages without backtracking.
• In Appendix C of her book Automata, Computability and Complexity with Applications, Elaine Rich lists and provides links to descriptions of various related representations for grammars of programming languages, namely: BNF, EBNF, and railroad (syntax) diagrams including Augmented Syntax Diagrams.
  

Usage notes

• Notes on using the ASDEditor .
• Restrictions on how ASD grammars should be written to be used with ASDParser.
• Setting and getting values of grammatical and semantic "features" during parsing with ASDParser
  
• Release notes for versions of ASDEditor, ASDParser, ASDTester, ASDCheck, and MergeGrammars.
• Known bugs in the software.

Implementation Details

• ASD grammar file format notes.
• ASDParser algorithm overview: An overview of the parsing algorithm used by ASDParser.
• ASDParser algorithm details
• javadoc documentation for the following packages: asd and digraphs which are in the asddigraphs.jar file, asdx which is in the asdx.jar file, and english which is in the english.jar file.  (See EnglishExamples.htm for a description of the english package.)

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