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Stdle #91 · classes · 2026-09-05

What does this TypeScript snippet output?

A past puzzle — fully playable. 4 attempts, hints on wrong guesses.

interface Shape { area(): number }
class Sq implements Shape { constructor(public s: number){} area(){return this.s**2;} }
console.log(new Sq(3) instanceof Sq, 'area' in new Sq(3));
Classes
4 attempts left

Answer & explanation