🧊 Remap

A module for transforming read-only maps in Roblox TypeScript. Intended for using ReadonlyMap in a state manager like Reflex.

All functions assume the map is immutable, and will return a new map if changes are made. Some functions will return the original map if a change is not necessary.

📦 Installation

``bash
npm install @rbxts/remap
pnpm add @rbxts/remap
yarn add @rbxts/remap
`

🔎 Example

`ts
import Remap from "@rbxts/remap";

let map = new ReadonlyMap();

map = Remap.assign(map, { foo: 1, bar: 2, baz: 3 }, { baz: Remap.None });
map = Remap.delete(map, "foo");
map = Remap.set(map, "baz", 3);
`

📚 API

$3

`ts
function set(object: ReadonlyMap, key: K, value: V): ReadonlyMap;

Remap.set(map, "foo", 1); // { foo: 1 }
`

Sets the value at key to value.

---

$3

`ts
function delete(object: ReadonlyMap, key: K): ReadonlyMap;

Remap.delete(map, "foo"); // deletes the entry at "foo"
`

Deletes the entry with the given key from the map.

---

$3

`ts
function deleteValue(object: ReadonlyMap, value: V): ReadonlyMap;

Remap.deleteValue(map, 1); // deletes the entry with the value 1
`

Deletes the entry with the given value from the map.

---

$3

`ts
function update(object: ReadonlyMap, key: K, updater: (value?: V) => V | undefined): ReadonlyMap;

Remap.update(map, "foo", (value = 0) => value + 1); // adds 1 to the value at "foo"
`

Updates the value at key with the result of updater. Returning undefined from updater will delete the entry.

---

$3

`ts
function map(object: ReadonlyMap, updater: (value: V, key: K) => R | undefined): ReadonlyMap;

Remap.map(map, (value, key) => value + 1); // adds 1 to each value
`

Updates each entry in the map with the result of updater. Returning undefined from updater will delete the entry.

---

$3

`ts
function filter(object: ReadonlyMap, predicate: (value: V, key: K) => boolean): ReadonlyMap;

Remap.filter(map, (value, key) => value > 1); // removes values less than 1
`

Deletes all entries from the map for which predicate returns false.

---

$3

`ts
function reduce(
object: ReadonlyMap,
reducer: (accumulator: R, value: V, key: K) => R,
initialValue: R,
): R;

Remap.reduce(map, (accumulator, value, key) => accumulator + value, 0); // sum of values
`

Reduces the map to a single value using reducer. The result of each call to reducer is passed as the first argument to the next call.

---

$3

`ts
function assign(map: ReadonlyMap, ...sources: ReadonlyMap[]): ReadonlyMap;

Remap.assign(map, { foo: 1, bar: 2, baz: 3 }, { baz: Remap.None }); // { foo: 1, bar: 2 }
`

Returns a new map with the keys and values from sources merged into map. Use the Remap.None symbol to mark a value for deletion.

If the key is a string, number, or symbol, you may pass objects to ...sources instead of maps.

---

$3

`ts
function clone(object: ReadonlyMap): Map;

Remap.clone(map).set("foo", 1);
`

Returns a mutable shallow copy of the map.

---

$3

`ts
function clear(object: ReadonlyMap): Map;

Remap.clear(map).set("foo", 1);
`

Returns an empty writable map of the same type as object.

---

$3

`ts
function omit(object: ReadonlyMap, ...keys: K[]): ReadonlyMap;

Remap.omit(map, "foo", "bar"); // { baz: 3 }
`

Returns a subset of the map excluding the keys specified.

---

$3

`ts
function pick(object: ReadonlyMap, ...keys: K[]): ReadonlyMap;

Remap.pick(map, "foo", "bar"); // { foo: 1, bar: 2 }
``

Returns a subset of the object with only the keys specified.

📄 License

Remap is available under the terms of the MIT license. See LICENSE for details.