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MapMap

import { Map, MapMap, mapMapBox, type MapMapBox } from 'amos';

MapMapBox stores a MapMap, a map whose values are Amos Map instances. Use it for two-level keyed state.

const matrixBox = mapMapBox('matrix', 'row', 'column', 0);

dispatch(matrixBox.setItemIn('a', 'x', 1));
dispatch(matrixBox.updateItemIn('a', 'x', (value) => value + 1));
select(matrixBox.getItemIn('a', 'x')); // 2

MapMap​

class MapMap<K extends ID, M extends Map<any, any>> extends Map<K, M>

MapMap supports all Map methods and delegated inner-map methods. Methods ending in In operate on the inner map at the outer key.

Mutation-style delegated methods:

setItemIn(outerKey, innerKey, value): this;
setAllIn(outerKey, items): this;
mergeItemIn(outerKey, innerKey, props): this;
mergeAllIn(outerKey, items): this;
updateItemIn(outerKey, innerKey, updater): this;
updateAllIn(outerKey, updater): this;
deleteItemIn(outerKey, innerKey): this;
deleteAllIn(outerKey, innerKeys): this;
clearIn(outerKey): this;
resetIn(outerKey, data): this;

Selector-style delegated methods:

getItemIn(outerKey, innerKey): V;
hasItemIn(outerKey, innerKey): boolean;
sizeIn(outerKey): number;
entriesIn(outerKey): IterableIterator<[string, V]>;
keysIn(outerKey): IterableIterator<string>;
valuesIn(outerKey): IterableIterator<V>;

setItem and setAll accept inner Map instances, plain dictionaries, or arrays of entries. Non-map values are converted by resetting the default inner map.

mapMapBox​

function mapMapBox<KO, KI, V>(
  key: string,
  outerKey: KO & ID,
  innerKey: KI & ID,
  defaultValue: V,
): MapMapBox<MapMap<IDOf<KO>, Map<IDOf<KI>, V>>>;

outerKey and innerKey are used for TypeScript inference. defaultValue is the inner map default value.

Mutations​

MapMapBox includes MapBox mutations and the delegated In mutations listed above.

setItemIn(outerKey: KO, innerKey: KI, value: V): Mutation<MapMap<KO, Map<KI, V>>>;
updateItemIn(outerKey: KO, innerKey: KI, updater: (value: V) => V): Mutation<MapMap<KO, Map<KI, V>>>;
deleteItemIn(outerKey: KO, innerKey: KI): Mutation<MapMap<KO, Map<KI, V>>>;
clearIn(outerKey: KO): Mutation<MapMap<KO, Map<KI, V>>>;

Selectors​

getItemIn(outerKey: KO, innerKey: KI): Selector<any, V>;
hasItemIn(outerKey: KO, innerKey: KI): Selector<any, boolean>;
sizeIn(outerKey: KO): Selector<any, number>;