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<!-- SPDX-License-Identifier: MIT -->
<!-- SPDX-FileCopyrightText: 2025-2026 Marcus Quinn -->
# Modern JavaScript (ES6-ES2025)

Use this file as the reference index: quick decision trees up front, then chapter links for the full corpus. The detailed material lives in `modern-javascript-skill/*.md`.

## Quick Reference

| File | Purpose |
|------|---------|
| [modern-javascript-skill/01-decision-trees.md](modern-javascript-skill/01-decision-trees.md) | Array methods, nullish handling, mutation vs copy |
| [modern-javascript-skill/02-es-versions.md](modern-javascript-skill/02-es-versions.md) | ES6 to ES2025 feature matrix |

## Reference Chapters

### ES Version References

| File | Purpose |
|------|---------|
| [modern-javascript-skill/es2016-es2017.md](modern-javascript-skill/es2016-es2017.md) | includes, async/await, Object.values/entries, string padding |
| [modern-javascript-skill/es2018-es2019.md](modern-javascript-skill/es2018-es2019.md) | rest/spread objects, flat/flatMap, RegExp named groups |
| [modern-javascript-skill/es2022-es2023.md](modern-javascript-skill/es2022-es2023.md) | .at(), .toSorted(), .toReversed(), .findLast(), class features |
| [modern-javascript-skill/es2024.md](modern-javascript-skill/es2024.md) | Object.groupBy, Promise.withResolvers, RegExp v flag |
| [modern-javascript-skill/es2025.md](modern-javascript-skill/es2025.md) | Set methods, iterator helpers, using/await using |
| [modern-javascript-skill/upcoming.md](modern-javascript-skill/upcoming.md) | Temporal API, Decorators, Decorator Metadata |

### Pattern References

| File | Purpose |
|------|---------|
| [modern-javascript-skill/promises.md](modern-javascript-skill/promises.md) | Promise fundamentals, async/await, combinators |
| [modern-javascript-skill/concurrency.md](modern-javascript-skill/concurrency.md) | Parallel, batched, pool patterns, retry, cancellation |
| [modern-javascript-skill/immutability.md](modern-javascript-skill/immutability.md) | Immutable data patterns, pure functions |
| [modern-javascript-skill/composition.md](modern-javascript-skill/composition.md) | Higher-order functions, memoization, monads |
| [modern-javascript-skill/cheatsheet.md](modern-javascript-skill/cheatsheet.md) | Quick syntax reference — destructuring, modernization patterns, all methods |

## Resources

- **ECMAScript Specification**: https://tc39.es/ecma262/
- **TC39 Proposals**: https://github.com/tc39/proposals
- **MDN Web Docs**: https://developer.mozilla.org/en-US/docs/Web/JavaScript
- **JavaScript.info**: https://javascript.info/
- **Can I Use**: https://caniuse.com
- **Node.js ES Compatibility**: https://node.green/
