antlr4 | ANother Tool for Language Recognition | Parser library

by antlr Java Version: 4.13.1-patch-1 License: BSD-3-Clause

X-Ray Key Features Code Snippets(10)Community Discussions(10)Vulnerabilities Install Support

kandi X-RAY | antlr4 Summary

antlr4 is a Java library typically used in Utilities, Parser applications. antlr4 has no bugs, it has no vulnerabilities, it has build file available, it has a Permissive License and it has high support. You can download it from GitHub, Maven.

ANTLR (ANother Tool for Language Recognition) is a powerful parser generator for reading, processing, executing, or translating structured text or binary files. It's widely used to build languages, tools, and frameworks. From a grammar, ANTLR generates a parser that can build parse trees and also generates a listener interface (or visitor) that makes it easy to respond to the recognition of phrases of interest.

Support

Quality

Security

License

Reuse

Support

antlr4 has a highly active ecosystem.

It has 14628 star(s) with 3081 fork(s). There are 367 watchers for this library.

There were 1 major release(s) in the last 12 months.

There are 707 open issues and 1417 have been closed. On average issues are closed in 206 days. There are 106 open pull requests and 0 closed requests.

It has a negative sentiment in the developer community.

The latest version of antlr4 is 4.13.1-patch-1

Quality

antlr4 has 0 bugs and 0 code smells.

Security

antlr4 has no vulnerabilities reported, and its dependent libraries have no vulnerabilities reported.

antlr4 code analysis shows 0 unresolved vulnerabilities.

There are 0 security hotspots that need review.

License

antlr4 is licensed under the BSD-3-Clause License. This license is Permissive.

Permissive licenses have the least restrictions, and you can use them in most projects.

Reuse

antlr4 releases are available to install and integrate.

Deployable package is available in Maven.

Build file is available. You can build the component from source.

antlr4 saves you 82485 person hours of effort in developing the same functionality from scratch.

It has 88823 lines of code, 8089 functions and 1102 files.

It has medium code complexity. Code complexity directly impacts maintainability of the code.

Top functions reviewed by kandi - BETA

kandi has reviewed antlr4 and discovered the below as its top functions. This is intended to give you an instant insight into antlr4 implemented functionality, and help decide if they suit your requirements.

Serializes the given ATN .
Serialize the ATN .
Shows a dialog .
Generate DOT graph for a given start state
Add feature codes to the map .
Computes the reachable configurations for the given input .
Optimize set of rules by removing all set transitions .
Run the lookahead .
Parse an escape point .
Entry point for the momar compiler .

Get all kandi verified functions for this library.

antlr4 Key Features

No Key Features are available at this moment for antlr4.

antlr4 Examples and Code Snippets

antlr4-tool,Getting Stated

TypeScript

Lines of Code : 39

License : Non-SPDX (NOASSERTION)

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npm install --save-dev antlr4-tool

npm install -S antlr4

#
# (TypeScript Only)
#
npm install -S @types/antlr4

"scripts": {
  "generate-parser": "antlr4-tool -o parser path/to/Grammar.g4"
}

npm run generate-parser


const antlr4 = require('antlr4'

GRUN for Antlr4: How to use?

JavaScript

Lines of Code : 15

License : Strong Copyleft (CC BY-SA 4.0)

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total_sales>qwe

ANTLR on  master [✘+?] 
➜ antlr4 qwe.g4      

ANTLR on  master [✘+?] 
➜ javac *.java

ANTLR on  master [✘+?] 
➜ grun qwe tokens -tokens < qwe.txt
[@0,0:10='total_sales',,1:0]
[@1,11:11='&g

Convert LaTeX Equation to SymPy [Julia] format

JavaScript

Lines of Code : 14

License : Strong Copyleft (CC BY-SA 4.0)

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# intall antlr4
using PyCall
run(`$(PyCall.python) -m pip install --upgrade antlr4-python3-runtime`)

# parse the expression
s = raw"\left[ \frac{(\theta - 1)(1 - \zeta(n,s))c\beta}{\theta w a } \right]"
using PyCall
latex = pyimport("symp

setting up ANTLR's CLASSPATH on macOS installed via HomeBrew

JavaScript

Lines of Code : 55

License : Strong Copyleft (CC BY-SA 4.0)

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grammar ElmerSolver;

// Parser Rules

// eostmt: ';' | CR;

statement: ';';

statement_list: statement*;

sections: section+ EOF;
// section: SectionName /* statement_list */ End;

// Lexer Rules

fragment DIGIT: [0-9];
Integer: DIGIT+;

ctx in ANTLR4 javascript visitor

JavaScript

Lines of Code : 38

License : Strong Copyleft (CC BY-SA 4.0)

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***************
* Hello world
***************

DECLAREPROGRAM  hw..

PRINT 'Hello World!'..

progm : stmt+ EOF;

import antlr4

from playground.MygrammarLexer import MygrammarLexer
from playg

Generating an AST report from Java source code without actually running it

Java

Lines of Code : 8

License : Strong Copyleft (CC BY-SA 4.0)

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$ antlr4 JavaLexer.g4 JavaParser.g4
$ javac Java*.java
$ grun Java compilationUnit -tree -gui

$ alias
alias antlr4='java -Xmx500M org.antlr.v4.Tool'
alias grun='java -Xmx500M org.antlr.v4.gui.TestRig'

How can a gradle build handle both antlr3 and antlr4 grammars?

JavaScript

Lines of Code : 31

License : Strong Copyleft (CC BY-SA 4.0)

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configurations{
  antlr3,
  antlr4
}

dependencies {
    antlr3 "org.antlr:antlr:3.5.2"
    antlr4 "org.antlr:antlr4:4.7.1" 

    compile "org.antlr:antlr-runtime:3.5.2"
    compile "org.antlr:antlr4-runtime:4.7.1" 
}

How to define in ANTLR4 a string with escaping boundary (like multipart mimetype)?

JavaScript

Lines of Code : 72

License : Strong Copyleft (CC BY-SA 4.0)

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lexer grammar DemoLexer;

@members {

def ahead(self, steps):
    """
    Returns the next `steps` characters ahead in the character-stream or None if
    there aren't `steps` characters ahead aymore
    """
    text = ""
    for n in rang

How to generate documentation for multiple files with Stardoc?

JavaScript

Lines of Code : 8

License : Strong Copyleft (CC BY-SA 4.0)

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load("//antlr:antlr4.bzl", _antlr4 = "antlr4")  
load("//antlr:antlr2.bzl", _antlr2 = "antlr2")  
load("//antlr:antlr3.bzl", _antlr3 = "antlr3")  

antlr4 = _antlr4  
antlr3 = _antlr3  
antlr2 = _antlr2

Exception in thread "main": –gui -tokens -tree

Java

Lines of Code : 3

License : Strong Copyleft (CC BY-SA 4.0)

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$ antlr4 run.g4
$ javac run*.java

Community Discussions

Trending Discussions on antlr4

Parse a string using ANTLR4

Antlr4 saying my rule is mutually left recursive with itself

Use source files generated by ANTLR

How to solve ANTLR error "Attribute references not allowed in lexer actions"

Spring Boot Logging to a File

Is there a way to extract tokens in order with ANTLR?

ANTLR4: How to hide a specific character?

How to run Spark SQL Thrift Server in local mode and connect to Delta using JDBC

ANTLR: how to debug a misidentified token

Match at least one element in sequence of optional elements (ANTLR)

QUESTION

Parse a string using ANTLR4

Asked 2022-Mar-24 at 15:56

Example: (CHGA/B234A/B231

...

ANSWER

Answered 2022-Mar-24 at 15:56

When you're confused why a certain parser rule is not being matched, always start with the lexer. Dump what tokens your lexer is producing on the stdout. Here's how you can do that:

Source https://stackoverflow.com/questions/71601965

QUESTION

Antlr4 saying my rule is mutually left recursive with itself

Asked 2022-Mar-17 at 07:00

I'm working on an assignment where we make a compiler for a simple language and we are using ANTLR4 for Java. After finally getting my grammar working i had to add some Java code to the language parser to build an AST. Here's where i get confused. Antlr is supposed to throw an error if rules are mutually left recursive and as i understand it it happens when one rule references another rule and the second rule reference the first rule. What i don't understand is why antlr is telling me that my rule is mutually left recursive with itself? Here is the error message i keep getting: error(119): PrevParser.g4::: The following sets of rules are mutually left-recursive [expr]. I looked around and noone seems to be having this issue. I did find someone saying that mutually left recursive rules have in common that their first token is another rule so i tried putting a regular . token right before the rule token and now it magically compiles. Why does it do that when the rule is only referencing itself? Heres the bit of code thats causing the issue:

...

ANSWER

Answered 2022-Mar-17 at 07:00

I've seems this on stackoverflow before (but can't find it anymore). This seems to be a bug that is caused by the parenthesis before the left-recursive expr. Just remove the parenthesis (which are redundant anyway).

So not:

Source https://stackoverflow.com/questions/71504800

QUESTION

Use source files generated by ANTLR

Asked 2022-Feb-26 at 17:03

I use ANTLR with the maven plugin to generate the source files. When creating them with mvn package they get correctly compiled and put together into target/generated-sources/antlr4, but from there I cannot access them in from my project.

My question is if I should be able to do this and import them somehow or if I need to move them from there to src.

...

ANSWER

Answered 2022-Feb-26 at 17:03

I found the answer: My pom.xml was missing generate-sources which was not mentioned in the Baeldung article I was following. After adding this to the execution tag it all worked and I could use it in my project!

Source https://stackoverflow.com/questions/71278368

QUESTION

How to solve ANTLR error "Attribute references not allowed in lexer actions"

Asked 2022-Feb-24 at 13:17

After reading Chapter 10 of "The Definitive ANTLR 4 Reference", I tried to write a simple analyzer to get lexical attributes, but I got an error. How can I get the lexical attributes?

...

ANSWER

Answered 2022-Feb-24 at 09:37

Try to separate the concerns of the lexer and other output matters: that's a main focus point of Antlr VS Bison/Flex. You can use for example visitor/listener patterns from the other chapters of the book.

Source https://stackoverflow.com/questions/71248471

QUESTION

Spring Boot Logging to a File

Asked 2022-Feb-16 at 14:49

In my application config i have defined the following properties:

...

ANSWER

Answered 2022-Feb-16 at 13:12

Acording to this answer: https://stackoverflow.com/a/51236918/16651073 tomcat falls back to default logging if it can resolve the location

Can you try to save the properties without the spaces.

Like this: logging.file.name=application.logs

Source https://stackoverflow.com/questions/71142413

QUESTION

Is there a way to extract tokens in order with ANTLR?

Asked 2022-Jan-13 at 19:50

Hi I'm currently trying to extract all tokens from ANTLR in C#, i'm using Antlr4.CodeGenerator and Antlr4.Runtime packages.

I want them structured in a way i can manipulate them, change their content and so on. I've tried using listeners and visitors and didn't got nowhere, so my intention is to structure the tokens in a list with objects containing their content, rule and token origin. My parser is validating the input correctly.

I've tried using MyLanguageLexer.GetAllTokens() but it returns empty. Also tried using CommonTokenStream.GetTokens() after executing .Fill(), it only returns the last token found which is an EOF, and I can't figure it out why.

I can iterate them in the ParseTree recursively but it's an unsafe approach to the problem and it bothers me the methods before didn't work.

This is my custom parsing class that currently returns the parsed tree, my objective is to return as the structure i'm triyng to build of the tokens.

...

ANSWER

Answered 2022-Jan-13 at 19:50

This works fine on my machine (with the ANTLR 4.9.3 C# runtime):

Source https://stackoverflow.com/questions/70701595

QUESTION

ANTLR4: How to hide a specific character?

Asked 2022-Jan-10 at 15:53

I am new to ANTLR4 and have a trouble.

I want to have the code accept integers with _ between digits, but the output would not include _ characters. For example: it would accept 12_34_5 and the expected token would be 12345.

Is there a way to do that in ANTLR4?

...

ANSWER

Answered 2022-Jan-10 at 15:53

I think what you mean by "output would not include _ characters" is to rewrite the text value of the recognized token. The "output" of a parse is a parse tree.

Use a lexer action.

CSharp:

Source https://stackoverflow.com/questions/70652185

QUESTION

How to run Spark SQL Thrift Server in local mode and connect to Delta using JDBC

Asked 2022-Jan-08 at 06:42

I'd like connect to Delta using JDBC and would like to run the Spark Thrift Server (STS) in local mode to kick the tyres.

I start STS using the following command:

...

ANSWER

Answered 2022-Jan-08 at 06:42

Once you can copy io.delta:delta-core_2.12:1.0.0 JAR file to $SPARK_HOME/lib and restart, this error goes away.

Source https://stackoverflow.com/questions/69862388

QUESTION

ANTLR: how to debug a misidentified token

Asked 2021-Dec-20 at 21:35

I am trying to implement a grammar in Antlr4 for a simple template engine. This engine consists of 3 different clauses:

IF ANSWERED ( variable )

END IF

Variable

Variable can be any upper or lowercase letter including white spaces. Both IF ANSWERED and END IF are always uppercase.

I have written the following grammar/lexer rules so far, but my problem is that IF ANSWERED keeps getting recognized as a Variable and not as 2 tokens IF and ANSWERED.

...

ANSWER

Answered 2021-Dec-20 at 21:35

Correct: ANTLR's lexer is greedy, and tries to consume as much as possible. That is why IF ANSWERED is tokenised as a TEXT token instead of 2 separate keywords. You'll need to change TEXT so that it does not match spaces.

Something like this could get you started:

Source https://stackoverflow.com/questions/70428170

QUESTION

Match at least one element in sequence of optional elements (ANTLR)

Asked 2021-Dec-18 at 22:55

Let's consider the following ANTLR4 grammar (minimal example):

...

ANSWER

Answered 2021-Dec-18 at 22:55

Not as simple as the hypothetical "at least one of" operator, but simpler than the solution you propose would be:

Source https://stackoverflow.com/questions/70407664

Community Discussions, Code Snippets contain sources that include Stack Exchange Network

Vulnerabilities

No vulnerabilities reported

Install antlr4

You can download it from GitHub, Maven.
You can use antlr4 like any standard Java library. Please include the the jar files in your classpath. You can also use any IDE and you can run and debug the antlr4 component as you would do with any other Java program. Best practice is to use a build tool that supports dependency management such as Maven or Gradle. For Maven installation, please refer maven.apache.org. For Gradle installation, please refer gradle.org .

Support

For any new features, suggestions and bugs create an issue on GitHub. If you have any questions check and ask questions on community page Stack Overflow .

Find more information at: