`keyof` for Map

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Description

const obj = {first: 'First Name', last: 'Last Name'};
type Keys = keyof typeof obj; // first | last

const map = new Map([
	[first, 'First Name'],
	[last: 'Last Name']
]);
type Keys = ????????

Contributor guide

Research direction

Use TypeScript's conditional types and mapped types to create a generic type that extracts the key type from a Map. For example, create a type `KeyOfMap<T>` that uses `T extends Map<infer K, any> ? K : never`. Provide examples and documentation.

Tech stack

typescript

Domain

developer experience

Issue type

Feature

DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.

2

Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.

1-3 hours

Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.

Active

ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.

Clear

Prerequisites

TypeScript

Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.

70