This is a playground to test JavaScript. It runs a completely standard copy of Node.js on a virtual server created just for you. Every one of npm’s 300,000+ packages are pre-installed, so try it out:
console.log('dsf')
const time = performance.now();
const finalizationRegistry = new FinalizationRegistry((value) => {
console.log(
`Promise ${value}. Time taken: ${(performance.now() - time).toFixed()}.`
);
});
let promiseWithoutResolve = new Promise((resolve) => {
setTimeout(() => {
console.log("Timeout for the promise that keeps no refs");
}, 100000);
});
finalizationRegistry.register(promiseWithoutResolve, " which keeps no references");
promiseWithoutResolve = null;
let promiseWithResolve = new Promise((resolve) => {
setTimeout(() => {
resolve();
}, 100000);
});
finalizationRegistry.register(promiseWithResolve , " which keeps resolve function");
promiseWithResolve = null;
let promiseWithThen = new Promise(() => {});
let then = promiseWithThen.then(() => {
console.log("then reached");
});
finalizationRegistry.register(promiseWithThen, " with `then` chain");
finalizationRegistry.register(then, " then callback");
promiseWithThen = then = null;
no comments
sign in to comment