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GOLD is a freeware parsing system that was designed to support multiple programming languages. A parser is a computer program or a component of a program that analyses the grammatical structure of an input, with respect to a given formal grammar, a process known as parsing. ...
The system uses the LALR algorithm for parsing and a DFA for the lexer. It designed around the principle of logically separating the process of generating the LALR and DFA parse tables and the actual implementation of the parsing algorithms. This allows parsers to be implemented in different programming languages while maintaining the same grammars and development process. Look-Ahead LR parsers or LALR parsers are a specialized form of LR parsers that can deal with more context-free grammars than Simple LR parsers but less than LR(1) parsers can. ...
In the theory of computation, a deterministic finite state machine or deterministic finite automaton (DFA) is a finite state machine where for each pair of state and input symbol there is one and only one transition to a next state. ...
Look-Ahead LR parsers or LALR parsers are a specialized form of LR parsers that can deal with more context-free grammars than Simple LR parsers but less than LR(1) parsers can. ...
In the theory of computation, a deterministic finite state machine or deterministic finite automaton (DFA) is a finite state machine where for each pair of state and input symbol there is one and only one transition to a next state. ...
Components
The GOLD system consists of three logical components, the "Builder", the "Engine", and a "Compiled Grammar Table" file type which functions as an intermediary between the first two.
Builder The Builder is the primary component and is used to read a grammar and construct the LALR and DFA parse tables. Essentially, the Builder performs the same table construction tasks as most compiler-compilers such as YACC and ANTLR. Look-Ahead LR parsers or LALR parsers are a specialized form of LR parsers that can deal with more context-free grammars than Simple LR parsers but less than LR(1) parsers can. ...
In the theory of computation, a deterministic finite state machine or deterministic finite automaton (DFA) is a finite state machine where for each pair of state and input symbol there is one and only one transition to a next state. ...
Yacc is a piece of computer software that serves as the standard parser generator on Unix systems. ...
The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ...
Once the LALR and DFA parse tables are successfully constructed, the Builder can save them into a Compiled Grammar Table file. This will be later used by the "Engine". Look-Ahead LR parsers or LALR parsers are a specialized form of LR parsers that can deal with more context-free grammars than Simple LR parsers but less than LR(1) parsers can. ...
In the theory of computation, a deterministic finite state machine or deterministic finite automaton (DFA) is a finite state machine where for each pair of state and input symbol there is one and only one transition to a next state. ...
In addition, the Builder can embed table information into a "skeleton program". These make use of templates designed for each different implementation of the Engine.
Currently, the Builder component is only available for Windows 32-bit operating systems. 1. ...
Compiled Grammar Table File The Compiled Grammar Table file is used to store table information generated by the Builder.
Engine The Engine component is written in a specific programming language and/or development platform. The Engine implements the LALR and DFA algorithms and interacts with the developers software. Look-Ahead LR parsers or LALR parsers are a specialized form of LR parsers that can deal with more context-free grammars than Simple LR parsers but less than LR(1) parsers can. ...
In the theory of computation, a deterministic finite state machine or deterministic finite automaton (DFA) is a finite state machine where for each pair of state and input symbol there is one and only one transition to a next state. ...
As different implementations of the Engine are created for different programming languages, the approach and design will vary. Since different programming languages use different approaches to designing programs, each implementation of the Engine will vary. As a result, an implementation of the Engine written for Visual Basic 6 will differ greatly from one written for ANSI C. Visual Basic (VB) is an event driven programming language and associated development environment from Microsoft. ...
ANSI C (Standard C) is a variant of the C programming language. ...
Grammars GOLD grammars are based directly on Backus-Naur Form, regular expressions, and set notation. The Backus-Naur form (BNF) (also known as Backus normal form) is a metasyntax used to express context-free grammars: that is, a formal way to describe formal languages. ...
In computing, a regular expression (abbreviated as regexp or regex, with plural forms regexps, regexes, or regexen) is a string that describes or matches a set of strings, according to certain syntax rules. ...
The following grammar defines the syntax for a minimal general-purpose programming language called "Simple".
"Name" = 'Simple' "Author" = 'Devin Cook' "Version" = '2.1' "About" = 'This is a very simple grammar designed for use in examples' "Case Sensitive" = False "Start Symbol" = <Statements> {String Ch 1} = {Printable} - [''] {String Ch 2} = {Printable} - ["] Identifier = {Letter}{AlphaNumeric}* ! String allows either single or double quotes StringLiteral = '' {String Ch 1}* '' | '"' {String Ch 2}* '"' NumberLiteral = {Number}+('.'{Number}+)? Comment Start = '/*' Comment End = '*/' Comment Line = '//' <Statements> ::= <Statements> <Statement> | <Statement> <Statement> ::= display <Expression> | display <Expression> read ID | assign ID '=' <Expression> | while <Expression> do <Statements> end | if <Expression> then <Statements> end | if <Expression> then <Statements> else <Statements> end <Expression> ::= <Expression> '>' <Add Exp> | <Expression> '<' <Add Exp> | <Expression> '<=' <Add Exp> | <Expression> '>=' <Add Exp> | <Expression> '==' <Add Exp> | <Expression> '<>' <Add Exp> | <Add Exp> <Add Exp> ::= <Add Exp> '+' <Mult Exp> | <Add Exp> '-' <Mult Exp> | <Add Exp> '&' <Mult Exp> | <Mult Exp> <Mult Exp> ::= <Mult Exp> '*' <Negate Exp> | <Mult Exp> '/' <Negate Exp> | <Negate Exp> <Negate Exp> ::= '-' <Value> | <Value> <Value> ::= Identifier | StringLiteral | NumberLiteral | '(' <Expression> ')'
Development Overview
1. Design the Grammar The first step consists of writing and testing a grammar for the language being parsed. The grammar can be written using any text editor - such as Notepad or the editor that is built into the Builder. At this stage, no coding is required.
Grammars are written using the GOLD Meta-language which is based on notation used by Backus-Naur Form and regular expressions. The Backus-Naur form (BNF) (also known as Backus normal form) is a metasyntax used to express context-free grammars: that is, a formal way to describe formal languages. ...
In computing, a regular expression (abbreviated as regexp or regex, with plural forms regexps, regexes, or regexen) is a string that describes or matches a set of strings, according to certain syntax rules. ...
2. Generate Skeleton Program and Compiled Grammar Table File Once the grammar is complete, it is analyzed by the Builder, the LALR and DFA parse tables are constructed, and any ambiguities or problems with the grammar are reported. Afterwards, the tables are saved to a Compiled Grammar Table file to be used later by a parsing engine. At this point, the GOLD Parser Builder is no longer needed. Look-Ahead LR parsers or LALR parsers are a specialized form of LR parsers that can deal with more context-free grammars than Simple LR parsers but less than LR(1) parsers can. ...
In the theory of computation, a deterministic finite state machine or deterministic finite automaton (DFA) is a finite state machine where for each pair of state and input symbol there is one and only one transition to a next state. ...
3. Select a Parsing Engine In the final stage, the tables are read by an Engine. At this point, the development process is dependant on the selected implementation language.
Supported Programming Languages An assembly language is a low-level language used in the writing of computer programs. ...
ANSI C (Standard C) is a variant of the C programming language. ...
The title given to this article is incorrect due to technical limitations. ...
Delphi is the primary programming language of Borland Delphi. ...
Java is an object-oriented programming language developed by Sun Microsystems in the early 1990s. ...
Pascal is an imperative computer programming language, developed in 1970 by Niklaus Wirth as a language particularly suitable for structured programming. ...
Python is a programming language created by Guido van Rossum in 1990. ...
Visual Basic (VB) is an event driven programming language and associated development environment from Microsoft. ...
Visual Basic . ...
This article or section does not cite its references or sources. ...
External Links - GOLD Parsing System Homepage
- GOLD Yahoo Group
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