jintr
v3.0.2
Published
A tiny JavaScript interpreter written in TypeScript.
Downloads
98,636
Maintainers
Readme
Note: This project was originally developed for use in YouTube.js.
Table of Contents
Installation
npm install jintr
Usage
Execute some JavaScript code:
// const Jinter = require('jintr').default;
import { Jinter } from 'jintr';
const code = `
function sayHiTo(person) {
console.log('Hi ' + person + '!');
}
sayHiTo('mom');
`
const jinter = new Jinter();
jinter.evaluate(code);
Inject your own functions, objects, etc:
import { Jinter } from 'jintr';
const jinter = new Jinter();
const code = `
console.log(new SomeClass().a);
console.log('hello'.toArray());
function myFn() {
console.log('[myFn]: Who called me?');
}
myFn();
`;
class SomeClass {
constructor() {
this.a = 'this is a test';
}
}
jinter.defineObject('SomeClass', SomeClass);
// Ex: str.toArray();
jinter.visitor.on('toArray', (node, visitor) => {
if (node.type === 'CallExpression' && node.callee.type === 'MemberExpression') {
const obj = visitor.visitNode(node.callee.object);
return obj.split('');
}
});
// Intercept function calls
jinter.visitor.on('myFn', (node) => {
if (node.type == 'CallExpression')
console.info('myFn was called!');
return '__continue_exec';
});
jinter.evaluate(code);
For more examples see /test
and /examples
.
API
evaluate(input: string)
Evaluates the given JavaScript code.
visitor
The node visitor. This is responsible for walking the AST and executing the nodes.
scope
Represents the global scope of the program.
License
Distributed under the MIT License.