Lrstar parser lexer generator

Author: i | 2025-04-24

Download LRSTAR Parser Lexer Generator latest version for Windows free. LRSTAR Parser Lexer Generator latest update: DFASTAR and DFAC lexer generators are included in the From comp.compilers newsgroup: Re: LRSTAR 3.0: LALR(k) parser generator lexer generator for C. Re: LRSTAR 3.0: LALR(k) parser generator lexer generator for C OJFord Tue, -0700 (PDT)

LRSTAR Parser Lexer Generator - CNET Download

Moo!Moo is a highly-optimised tokenizer/lexer generator. Use it to tokenize your strings, before parsing 'em with a parser like nearley or whatever else you're into.FastConvenientuses Regular Expressionstracks Line Numbershandles Keywordssupports Statescustom Errorsis even Iterablehas no dependencies4KB minified + gzippedMoo!Is it fast?Yup! Flying-cows-and-singed-steak fast.Moo is the fastest JS tokenizer around. It's ~2–10x faster than most other tokenizers; it's a couple orders of magnitude faster than some of the slower ones.Define your tokens using regular expressions. Moo will compile 'em down to a single RegExp for performance. It uses the new ES6 sticky flag where possible to make things faster; otherwise it falls back to an almost-as-efficient workaround. (For more than you ever wanted to know about this, read adventures in the land of substrings and RegExps.)You might be able to go faster still by writing your lexer by hand rather than using RegExps, but that's icky.Oh, and it avoids parsing RegExps by itself. Because that would be horrible.UsageFirst, you need to do the needful: $ npm install moo, or whatever will ship this code to your computer. Alternatively, grab the moo.js file by itself and slap it into your web page via a tag; moo is completely standalone.Then you can start roasting your very own lexer/tokenizer: const moo = require('moo') let lexer = moo.compile({ WS: /[ \t]+/, comment: /\/\/.*?$/, number: /0|[1-9][0-9]*/, string: /"(?:\\["\\]|[^\n"\\])*"/, lparen: '(', rparen: ')', keyword: ['while', 'if', 'else', 'moo', 'cows'], NL: { match: /\n/, lineBreaks: true }, })And now throw some text at it: lexer.reset('while (10) cows\nmoo') lexer.next()

LRSTAR Parser Lexer Generator for Windows - CNET Download

README - pyLRp python LR(1) parser generatorAuthor: Sebastian Riese The sample files show how to use the parser generator. But are out ofdate at the moment. More documentation will follow. The parsergenerator is written in python3, but it can generate both python2 andpython3 parsers.The generated parsers are standalone modules.usage: pyLRp.py [-h] [-o OFILE] [-l] [-L] [-g] [--print-lextable] [-D] [-d] [-f] [-q] [-T] [-3 | -2] infileA pure python LALR(1)/LR(1) parser generator and lexer generator.positional arguments: infile The parser specification to processoptional arguments: -h, --help show this help message and exit -o OFILE, --output-file OFILE Set the output file to OFILE [default: derived from infile] -l, --line-tracking Enable line tracking in the generated parser -L, --lalr Generate a LALR(1) parser instead of a LR(1) parser -g, --print-graph Print the LR state graph to stdout --print-lextable Print the lextables to stdout -D, --not-deduplicate Compress tables by reusing identical lines -d, --debug Write debug information to the generated file -f, --fast Fast run: generates larger and possibly slower parsers, but takes less time -q, --quiet Print less info -T, --trace Generate a parser that prints out a trace of its state -3, --python3 Generate python3 compatible parser [default] -2, --python2 Generate python2 compatible parserContributors------------Jonas Wielicki (Python 3 support, testing)Testing-------To run the TestSuite run[pyLR1]$ python3 -m unittest discover -s test -vLicense-------Copyright 2009, 2010, 2012 Sebastian RiesePermission is hereby granted, free of charge, to any person obtaining a copyof this software and associated documentation files (the "Software"), to dealin the Software without restriction, including without limitation the rightsto use, copy, modify, merge, publish, distribute, sublicense, and/or sellcopies of the Software, and to permit persons to whom the Software isfurnished to do so, subject to the following conditions:The above copyright notice and this permission notice shall be included inall copies or substantial portions of the Software.THE

LRSTAR Parser Lexer Generator para Windows - CNET

Skip to content Navigation Menu GitHub Copilot Write better code with AI Security Find and fix vulnerabilities Actions Automate any workflow Codespaces Instant dev environments Issues Plan and track work Code Review Manage code changes Discussions Collaborate outside of code Code Search Find more, search less Explore Learning Pathways Events & Webinars Ebooks & Whitepapers Customer Stories Partners Executive Insights GitHub Sponsors Fund open source developers The ReadME Project GitHub community articles Enterprise platform AI-powered developer platform Pricing Provide feedback Saved searches Use saved searches to filter your results more quickly //voltron/issues_fragments/issue_layout;ref_cta:Sign up;ref_loc:header logged out"}"> Sign up Notifications You must be signed in to change notification settings Fork 3.3k Star 17.7k DescriptionVersion: ANTLR4 JavaOS: Windows 11 Pro 64bitANTLR Tool version 4.4 used for code generation does not match the current runtime version 4.11.1Exception in thread "main" java.lang.ExceptionInInitializerErrorat main.horizon.main(horizon.java:22)Caused by: java.lang.UnsupportedOperationException: java.io.InvalidClassException: org.antlr.v4.runtime.atn.ATN; Could not deserialize ATN with version 3 (expected 4).at org.antlr.v4.runtime.atn.ATNDeserializer.deserialize(ATNDeserializer.java:56)at org.antlr.v4.runtime.atn.ATNDeserializer.deserialize(ATNDeserializer.java:48)at target.generatedsources.antlr4.horizonLexer.(horizonLexer.java:188)... 1 moreCaused by: java.io.InvalidClassException: org.antlr.v4.runtime.atn.ATN; Could not deserialize ATN with version 3 (expected 4).... 4 moreMain class code:package main;import java.io.File;import java.io.IOException;import java.util.Scanner;import org.antlr.v4.runtime.CharStream;import org.antlr.v4.runtime.CharStreams;import org.antlr.v4.runtime.CommonTokenStream;import target.generatedsources.antlr4.horizonLexer;import target.generatedsources.antlr4.horizonParser;public class horizon { public static void main(String[] args) throws IOException { Scanner scanner = new Scanner(System.in); System.out.print("Enter a horizon file: "); String fileName = scanner.next(); File temp = new File(fileName); if (temp.exists()) { CharStream charStream = CharStreams.fromFileName(fileName); horizonLexer lexer = new horizonLexer(charStream); CommonTokenStream commonTokenStream = new CommonTokenStream(lexer); horizonParser parser = new horizonParser(commonTokenStream); } else { System.out.println("The file "" + fileName + "" doesn't exist!"); System.exit(1); } }}. Download LRSTAR Parser Lexer Generator latest version for Windows free. LRSTAR Parser Lexer Generator latest update: DFASTAR and DFAC lexer generators are included in the

New LRSTAR 4.0 Parser Lexer Generator just released.

Method name, parameter list, and throws clause like so:methodDeclarator : Identifier '(' formalParameterList? ')' dims? ;And so Java8BaseListener has a method enterMethodDeclarator which will be invoked each time this pattern is encountered.So, let’s override enterMethodDeclarator, pull out the Identifier, and perform our check:public class UppercaseMethodListener extends Java8BaseListener { private List errors = new ArrayList(); // ... getter for errors @Override public void enterMethodDeclarator(Java8Parser.MethodDeclaratorContext ctx) { TerminalNode node = ctx.Identifier(); String methodName = node.getText(); if (Character.isUpperCase(methodName.charAt(0))) { String error = String.format("Method %s is uppercased!", methodName); errors.add(error); } }}5.4. TestingNow, let’s do some testing. First, we construct the lexer:String javaClassContent = "public class SampleClass { void DoSomething(){} }";Java8Lexer java8Lexer = new Java8Lexer(CharStreams.fromString(javaClassContent));Then, we instantiate the parser:CommonTokenStream tokens = new CommonTokenStream(lexer);Java8Parser parser = new Java8Parser(tokens);ParseTree tree = parser.compilationUnit();And then, the walker and the listener:ParseTreeWalker walker = new ParseTreeWalker();UppercaseMethodListener listener= new UppercaseMethodListener();Lastly, we tell ANTLR to walk through our sample class:walker.walk(listener, tree);assertThat(listener.getErrors().size(), is(1));assertThat(listener.getErrors().get(0), is("Method DoSomething is uppercased!"));6. Building Our GrammarNow, let’s try something just a little bit more complex, like parsing log files:2018-May-05 14:20:18 INFO some error occurred2018-May-05 14:20:19 INFO yet another error2018-May-05 14:20:20 INFO some method started2018-May-05 14:20:21 DEBUG another method started2018-May-05 14:20:21 DEBUG entering awesome method2018-May-05 14:20:24 ERROR Bad thing happenedBecause we have a custom log format, we’re going to first need to create our own grammar.6.1. Prepare a Grammar FileFirst, let’s see if we can create a mental map of what each log line looks like in our file. Or if we go one more level deep, we might say: := …And so on. It’s important to consider this so we can decide at what level of granularity we want to parse the text.A grammar file is basically a set of lexer and parser rules. Simply put, lexer rules describe the syntax of the grammar while parser rules describe the semantics.Let’s start by defining fragments which are reusable building blocks for lexer rules.fragment DIGIT : [0-9];fragment TWODIGIT : DIGIT DIGIT;fragment LETTER : [A-Za-z];Next, let’s define the remainings lexer rules:DATE : TWODIGIT TWODIGIT '-' LETTER LETTER LETTER '-' TWODIGIT;TIME : TWODIGIT ':' TWODIGIT ':' TWODIGIT;TEXT : LETTER+ ;CRLF : '\r'? '\n' |

LRSTAR Parser Lexer Generator para Windows - CNET Download

Will throw an Error; since it doesn't know what else to do.If you prefer, you can have moo return an error token instead of throwing an exception. The error token will contain the whole of the rest of the buffer. moo.compile({ // ... myError: moo.error, }) moo.reset('invalid') moo.next() // -> { type: 'myError', value: 'invalid', text: 'invalid', offset: 0, lineBreaks: 0, line: 1, col: 1 } moo.next() // -> undefinedYou can have a token type that both matches tokens and contains error values. moo.compile({ // ... myError: {match: /[\$?`]/, error: true}, })Formatting errorsIf you want to throw an error from your parser, you might find formatError helpful. Call it with the offending token:throw new Error(lexer.formatError(token, "invalid syntax"))It returns a string with a pretty error message.Error: invalid syntax at line 2 col 15: totally valid `syntax` ^IterationIterators: we got 'em. for (let here of lexer) { // here = { type: 'number', value: '123', ... } }Create an array of tokens. let tokens = Array.from(lexer);Use itt's iteration tools with Moo. for (let [here, next] of itt(lexer).lookahead()) { // pass a number if you need more tokens // enjoy! }TransformMoo doesn't allow capturing groups, but you can supply a transform function, value(), which will be called on the value before storing it in the Token object. moo.compile({ STRING: [ {match: /"""[^]*?"""/, lineBreaks: true, value: x => x.slice(3, -3)}, {match: /"(?:\\["\\rn]|[^"\\])*?"/, lineBreaks: true, value: x => x.slice(1, -1)}, {match: /'(?:\\['\\rn]|[^'\\])*?'/, lineBreaks: true, value: x => x.slice(1, -1)}, ], // ... })ContributingDo check the

LRSTAR 3.0: LALR(k) parser generator lexer generator for C

Maleenimaleeni is a lexer generator for golang. maleeni also provides a command to perform lexical analysis to allow easy debugging of your lexical specification.InstallationCompiler:$ go install github.com/nihei9/maleeni/cmd/maleeni@latestCode Generator:$ go install github.com/nihei9/maleeni/cmd/maleeni-go@latestUsage1. Define your lexical specificationFirst, define your lexical specification in JSON format. As an example, let's write the definitions of whitespace, words, and punctuation.{ "name": "statement", "entries": [ { "kind": "whitespace", "pattern": "[\\u{0009}\\u{000A}\\u{000D}\\u{0020}]+" }, { "kind": "word", "pattern": "[0-9A-Za-z]+" }, { "kind": "punctuation", "pattern": "[.,:;]" } ]}Save the above specification to a file. In this explanation, the file name is statement.json.⚠️ The input file must be encoded in UTF-8.2. Compile the lexical specificationNext, generate a DFA from the lexical specification using maleeni compile command.$ maleeni compile statement.json -o statementc.json3. Debug (Optional)If you want to make sure that the lexical specification behaves as expected, you can use maleeni lex command to try lexical analysis without having to generate a lexer. maleeni lex command outputs tokens in JSON format. For simplicity, print significant fields of the tokens in CSV format using jq command.⚠️ An encoding that maleeni lex and the driver can handle is only UTF-8.$ echo -n 'The truth is out there.' | maleeni lex statementc.json | jq -r '[.kind_name, .lexeme, .eof] | @csv'"word","The",false"whitespace"," ",false"word","truth",false"whitespace"," ",false"word","is",false"whitespace"," ",false"word","out",false"whitespace"," ",false"word","there",false"punctuation",".",false"","",trueThe JSON format of tokens that maleeni lex command prints is as follows:FieldTypeDescriptionmode_idintegerAn ID of a lex mode.mode_namestringA name of a lex mode.kind_idintegerAn ID of a kind. This is unique among all modes.mode_kind_idintegerAn ID of a lexical kind. This is unique only within a mode. Note that you need to use kind_id field if you want to identify a kind across all modes.kind_namestringA name of a lexical kind.rowintegerA row number where a lexeme appears.colintegerA column number where a lexeme appears. Note that col is counted in code points, not bytes.lexemearray of integersA byte sequense of a lexeme.eofboolWhen this field is true, it means the token is the EOF token.invalidboolWhen this field is true, it means the token is an error token.4. Generate the lexerUsing maleeni-go command, you can generate a source code of the lexer to recognize your lexical specification.$ maleeni-go statementc.jsonThe above command generates the lexer and saves it to statement_lexer.go file. By default, the file name will be {spec name}_lexer.json. To use the lexer, you need to call NewLexer function defined in statement_lexer.go. The following code is a simple example. In this example, the lexer reads a source code from stdin and writes the result, tokens, to stdout.package mainimport ( "fmt" "os")func main() { lex, err := NewLexer(NewLexSpec(), os.Stdin) if err != nil { fmt.Fprintln(os.Stderr, err) os.Exit(1) } for { tok, err := lex.Next() if err != nil { fmt.Fprintln(os.Stderr, err) os.Exit(1) } if tok.EOF { break } if tok.Invalid { fmt.Printf("invalid: %#v\n", string(tok.Lexeme)) } else { fmt.Printf("valid: %v: %#v\n", KindIDToName(tok.KindID), string(tok.Lexeme)) } }}Please save the above source code to main.go and create a directory structure like the one below./project_root├── statement_lexer.go ... Lexer generated from the compiled lexical specification (the result of `maleeni-go`).└── main.go .............. Caller of the lexer.Now, you can perform. Download LRSTAR Parser Lexer Generator latest version for Windows free. LRSTAR Parser Lexer Generator latest update: DFASTAR and DFAC lexer generators are included in the From comp.compilers newsgroup: Re: LRSTAR 3.0: LALR(k) parser generator lexer generator for C. Re: LRSTAR 3.0: LALR(k) parser generator lexer generator for C OJFord Tue, -0700 (PDT)