Loads a ANTLR4 grammar file and compiles it to JavaScript.
npm install antlr4-webpack-loaderLoads an ANTLR4 grammar file (.g4) and compiles it to JavaScript.
``js`
import {
MyGrammarLexer,
MyGrammarParser,
MyGrammarListener,
MyGrammarVisitor
} from './MyGrammar.g4';
Add the ANTLR4 JavaScript runtime as a dependency: npm install --save antlr4.
Configure webpack.config.js by adding antlr4-webpack-loader:
`js`
module.exports = {
module: {
rules: [
{ test: /\.g4/, loader: 'antlr4-webpack-loader' }
]
}
};
A grammar file named MyGrammar.g4 with a rule named myStartRule can be loaded in used in the following way:
`js
import { InputStream, CommonTokenStream } from 'antlr4/index';
import { MyGrammarLexer, MyGrammarParser, MyGrammarVisitor } from './MyGrammar.g4';
class MyVisitor extends MyGrammarVisitor {
visitMyStartRule(ctx) { ... }
...
}
const input = ...; // Load string content
const lexer = new MyGrammarLexer(new InputStream(input));
const parser = new MyGrammarParser(new CommonTokenStream(lexer));
const result = new MyVisitor().visit(parser.myStartRule());
``