Class DynMapReducer<K, T>

Provides a managed Map with non-destructive reducing / filtering / sorting capabilities with subscription / Svelte store support allowing for a Map to be treated like an iterable list.

Note:

The default type unknown ensures stricter type checking, preventing unintended operations on the data.
If the type of data is known, explicitly specify the generic type to improve clarity and maintainability:

Example

const mapReducer = new DynMapReducer<number, string>(
    new Map([
        [1, 'banana'],
        [2, 'apple'],
        [3, 'cherry'],
    ])
);

console.log([...mapReducer]); // Output: ['banana', 'apple', 'cherry']

// Sort values alphabetically.
mapReducer.sort.set((a, b) => a.localeCompare(b));

console.log([...mapReducer]); // Output: ['apple', 'banana', 'cherry']

Type Parameters

K = unknown
unknown - Key type. Defaults to unknown to enforce type safety when no type is specified.
T = unknown
unknown - Type of data. Defaults to unknown to enforce type safety when no type is specified.

Index

Constructors

constructor

new DynMapReducer<K = unknown, T = unknown>(
data?: Map<K, T> | MapReducer<K, T>,
): DynMapReducer<K, T>
Initializes DynMapReducer. Any iterable is supported for initial data. Take note that if data is an array it will be used as the host array and not copied. All non-array iterables otherwise create a new array / copy.
Type Parameters
- K = unknown
  unknown - Key type.
- T = unknown
  unknown - Type of data.
Parameters
- Optionaldata: Map<K, T> | MapReducer<K, T>
  Data iterable to store if array or copy otherwise.
Returns DynMapReducer<K, T>

Accessors

data

get data(): Map<K, T>
Returns the internal data of this instance. Be careful!

Note: When a map is set as data then that map is used as the internal data. If any changes are performed to the data externally do invoke update via DynMapReducer.index with true to recalculate the index and notify all subscribers.

Returns Map<K, T>
The internal data.

derived

get derived(): DynReducer.API.DerivedMap<K, T>
Returns DynReducer.API.DerivedMap<K, T>
Derived public API.

destroyed

get destroyed(): boolean
Returns boolean
Returns whether this instance is destroyed.

filters

get filters(): DynReducer.API.Filters<T>
Returns DynReducer.API.Filters<T>
The filters adapter.

index

get index(): Index<K>
Returns Index<K>
Returns the Indexer public API; is also iterable.

length

get length(): number
Returns number
Returns the main data items or indexed items length.

reversed

get reversed(): boolean
Returns boolean
Returns current reversed state.
set reversed(reversed: boolean): void
Sets reversed state and notifies subscribers.
Parameters
- reversed: boolean
  New reversed state.
Returns void

sort

get sort(): DynReducer.API.Sort<T>
Returns DynReducer.API.Sort<T>
The sort adapter.

Methods

[iterator]

"[iterator]"(): IterableIterator<T>
Provides an iterator for data stored in DynMapReducer.

Returns IterableIterator<T>
Iterator for data stored in DynMapReducer.

destroy

destroy(): void
Removes all derived reducers, subscriptions, and cleans up all resources.

Returns void

`Protected`initialize

initialize(optionsRest?: { [key: string]: any }): void
Protected
Provides a callback for custom reducers to initialize any data / custom configuration. Depending on the consumer of dynamic-reducer this may be utilized allowing child classes to avoid implementing the constructor.
Parameters
- OptionaloptionsRest: { [key: string]: any }
  Any additional custom options passed beyond DynReducer.Options.Common.
Returns void

setData

setData(data: Map<K, T>, replace?: boolean): void
Removes internal data and pushes new data. This does not destroy any initial array set to internal data unless replace is set to true.
Parameters
- data: Map<K, T>
  New data to set to internal data.
- Optionalreplace: boolean
  New data to set to internal data.
Returns void

subscribe(handler: (value: this) => void): () => void
Add a subscriber to this DynMapReducer instance.
Parameters
- handler: (value: this) => void
  Callback function that is invoked on update / changes. Receives this reference.
Returns () => void
Unsubscribe function.

Class DynMapReducer<K, T>

Example

Type Parameters

Index

Constructors

Accessors

Methods

Constructors

constructor

Type Parameters

Parameters

Returns DynMapReducer<K, T>

Accessors

data

Returns Map<K, T>

derived

Returns DynReducer.API.DerivedMap<K, T>

destroyed

Returns boolean

filters

Returns DynReducer.API.Filters<T>

index

Returns Index<K>

length

Returns number

reversed

Returns boolean

Parameters

Returns void

sort

Returns DynReducer.API.Sort<T>

Methods

[iterator]

Returns IterableIterator<T>

destroy

Returns void

Protectedinitialize

Parameters

Returns void

setData

Parameters

Returns void

subscribe

Parameters

Returns () => void

Settings

On This Page

`Protected`initialize