CHALLENGE
async function fetchData(id) {
if (id <= 0) throw new Error("Invalid ID");
return { id, value: id * 10 };
}
async function process() {
const results = await Promise.allSettled([
fetchData(1),
fetchData(-1),
fetchData(3),
]);
results.forEach(({ status, value, reason }) => {
if (status === "fulfilled") {
console.log(`✅ ${value.id}: ${value.value}`);
} else {
console.log(`❌ ${reason.message}`);
}
});
}
process();❤5👍1🔥1
What is the output?
Anonymous Quiz
25%
✅ 1: 10 ❌ Error: Invalid ID ✅ 3: 30
47%
✅ 1: 10 ❌ Invalid ID ✅ 3: 30
23%
✅ 1: 10 ✅ 3: 30
4%
❌ Invalid ID ✅ 1: 10 ✅ 3: 30
❤2👍1
CHALLENGE
const compose = (...fns) => x => fns.reduceRight((acc, fn) => fn(acc), x);
const pipe = (...fns) => x => fns.reduce((acc, fn) => fn(acc), x);
const double = x => x * 2;
const addTen = x => x + 10;
const square = x => x * x;
const negate = x => -x;
const transform1 = compose(negate, square, addTen, double);
const transform2 = pipe(negate, square, addTen, double);
console.log(transform1(3));
console.log(transform2(3));
❤5👍2🔥1
🤔2👍1🔥1
CHALLENGE
const setA = new Set([1, 2, 3, 4, 5]);
const setB = new Set([3, 4, 5, 6, 7]);
const union = new Set([...setA, ...setB]);
const intersection = new Set([...setA].filter(x => setB.has(x)));
const differenceAB = new Set([...setA].filter(x => !setB.has(x)));
const symmetricDiff = new Set(
[...setA, ...setB].filter(x => !(setA.has(x) && setB.has(x)))
);
console.log([...union].join(','));
console.log([...intersection].join(','));
console.log([...differenceAB].join(','));
console.log([...symmetricDiff].join(','));
🔥5❤2👍1
What is the output?
Anonymous Quiz
24%
1,2,3,4,5,6,7 3,4,5 6,7 1,2,6,7
46%
1,2,3,4,5,6,7 3,4,5 1,2 1,2,6,7
20%
1,2,3,4,5,6,7 4,5 1,2 1,2,6,7
11%
1,2,3,4,5,6,7 3,4,5 1,2,3 1,2,3,6,7
❤1
Vite+ is the Vite team’s ‘unified toolchain’ that brings Vite, Vitest, Oxlint, and similar tools together under a single vp command, whether for running a dev server, tests, formatting, or bundling.
VoidZero
Please open Telegram to view this post
VIEW IN TELEGRAM
❤6👍4🔥2
CHALLENGE
const compose = (...fns) => x => fns.reduceRight((acc, fn) => fn(acc), x);
const pipe = (...fns) => x => fns.reduce((acc, fn) => fn(acc), x);
const double = x => x * 2;
const addTen = x => x + 10;
const square = x => x ** 2;
const negate = x => -x;
const transform1 = compose(negate, square, addTen, double);
const transform2 = pipe(negate, square, addTen, double);
console.log(transform1(3));
console.log(transform2(3));
🔥3❤2🤩1
👍3❤1🤩1🤣1
With Eloquent JavaScript and ProseMirror under his belt, not many people know more about JavaScript and making good editor controls than Marijn. Modular, supports collaborative editing, and thoughtfully built. Live demo and how to get started.
Marijn Haverbeke
Please open Telegram to view this post
VIEW IN TELEGRAM
❤7🔥3
A minor release whose headline feature is the (experimental) implementation of package maps (which let Node resolve packages from a static JSON file rather than walking node_modules). Matteo Collina’s node:vfs subsystem also begins to make an appearance.
Antoine du Hamel
Please open Telegram to view this post
VIEW IN TELEGRAM
👍6❤3🔥1
CHALLENGE
class Pipeline {
#value;
#steps = [];
constructor(value) {
this.#value = value;
}
map(fn) {
this.#steps.push({ type: 'map', fn });
return this;
}
filter(fn) {
this.#steps.push({ type: 'filter', fn });
return this;
}
execute() {
return this.#steps.reduce((acc, step) => {
if (step.type === 'map') return acc.map(step.fn);
if (step.type === 'filter') return acc.filter(step.fn);
return acc;
}, this.#value);
}
}
const result = new Pipeline([1, 2, 3, 4, 5, 6])
.filter(x => x % 2 === 0)
.map(x => x ** 2)
.filter(x => x > 10)
.map(x => x - 1)
.execute();
console.log(result);👍5❤2🔥1
❤1🔥1
A new framework from Vercel that provides Next.js-esque structure for building AI-powered agents using TypeScript and Markdown. It's quite Vercel-flavored by default, but I found you can run it entirely independently of Vercel with a few settings tweaks and your own keys. Project homepage.
Vercel
Please open Telegram to view this post
VIEW IN TELEGRAM
❤4🔥2
CHALLENGE
console.log('start');
setTimeout(() => console.log('timeout 1'), 0);
Promise.resolve()
.then(() => {
console.log('promise 1');
setTimeout(() => console.log('timeout 2'), 0);
})
.then(() => console.log('promise 2'));
setTimeout(() => console.log('timeout 3'), 0);
queueMicrotask(() => console.log('microtask'));
console.log('end');❤5🔥3👍2
What is the output?
Anonymous Quiz
29%
start end promise 1 microtask promise 2 timeout 1 timeout 3 timeout 2
39%
start end promise 1 promise 2 microtask timeout 1 timeout 3 timeout 2
20%
start end microtask promise 1 promise 2 timeout 1 timeout 2 timeout 3
12%
start end timeout 1 timeout 3 promise 1 microtask promise 2 timeout 2
❤4🔥1
CHALLENGE
const curry = (fn) => {
const arity = fn.length;
return function curried(...args) {
if (args.length >= arity) {
return fn(...args);
}
return (...moreArgs) => curried(...args, ...moreArgs);
};
};
const volume = (l, w, h) => l * w * h;
const curriedVolume = curry(volume);
const withLength5 = curriedVolume(5);
const withLength5Width3 = withLength5(3);
console.log(typeof withLength5);
console.log(typeof withLength5Width3);
console.log(withLength5Width3(2));
console.log(curriedVolume(5)(3)(2) === withLength5(3)(2));
❤4🔥3👍1
What is the output?
Anonymous Quiz
24%
function function 30 false
27%
object function 30 true
34%
function function 30 true
16%
function number 30 true
🔥2❤1
CHALLENGE
const obj = {
name: "Quantum",
regular: function () {
return this.name;
},
arrow: () => {
return this?.name;
},
nested: function () {
const inner = () => this.name;
return inner();
},
};
console.log(obj.regular());
console.log(obj.arrow());
console.log(obj.nested());❤4👍4🔥4
What is the output?
Anonymous Quiz
18%
undefined undefined Quantum
28%
Quantum Quantum Quantum
26%
Quantum undefined undefined
28%
Quantum undefined Quantum
🔥2🤣2
CHALLENGE
const flags = {
READ: 0b0001,
WRITE: 0b0010,
EXECUTE: 0b0100,
DELETE: 0b1000,
};
const userPermissions = flags.READ | flags.WRITE | flags.EXECUTE;
const adminPermissions = userPermissions | flags.DELETE;
const canDelete = (adminPermissions & flags.DELETE) !== 0;
const readOnly = userPermissions & ~flags.WRITE;
const toggled = userPermissions ^ flags.EXECUTE;
const shifted = (flags.DELETE << 2) | (flags.READ >> 0);
console.log(canDelete, readOnly, toggled, shifted);❤3👍2🔥1