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Collections

@starbeam/collections defines reactive versions of ordinary JavaScript objects and built-in collections. Use it for collection-shaped and object-shaped root state.

For the concept guide, start with Collections and objects.

Install

pnpm add @starbeam/collections

import { reactive } from "@starbeam/collections";

Recommended helpers

Helper	Returns	Use for
`reactive.Map<K, V>()`	`Map<K, V>`	keyed records, registries, caches, carts
`reactive.Set<T>()`	`Set<T>`	membership, selections, tags
`reactive.array<T>(values)`	`T[]`	ordered list state
`reactive.object<T>(value)`	`T`	object-shaped state
`reactive.WeakMap<K, V>()`	`WeakMap<K, V>`	object-keyed storage with weak ownership
`reactive.WeakSet<T>()`	`WeakSet<T>`	weak object membership

reactive.Map() and reactive.Set() create empty collections. Add entries with the normal JavaScript APIs.

reactive.object() and reactive.array() wrap an initial object or array and return the same JavaScript/TypeScript surface.

Notes

Prefer the named reactive import in user-facing examples.
Keep reactive storage private inside domain objects when the collection is an implementation detail.
Use Resources and lifecycle when the work has setup, sync, cleanup, or finalization.