Advanced review practice

Opening your lesson

Bring the advanced contracts together on one final set of independent requests. You will report every asynchronous outcome, trace cleanup, filter capabilities, patch a booking, select an available route, normalize an unknown error, validate an event name, and account for retry duration. Each task uses concepts already introduced in this level.

Choose the data and type checks that belong to the contract. A string containing a valid event is not necessarily a valid event. A missing label and an empty label can have different meanings. A failed asynchronous operation still needs cleanup. The hidden fixtures return to these distinctions because they often disappear when code is shortened without tracing its behavior. Keep your implementation readable enough that you could explain it during a review.

async function solve(values:string[]):Promise<string[]> { const jobs=values.map(value=>value.startsWith("!")?Promise.reject(value.slice(1)):Promise.resolve(value)); const results=await Promise.allSettled(jobs); return results.map(result=>result.status==="fulfilled"?"fulfilled:"+result.value:"rejected:"+String(result.reason)); }

A complete implementation for the first scenario; trace its input before editing.

Choose your character

Your Work Gym account