Lookup Class

Package: @esfx/iter-lookup

Declaration

export declare class Lookup<K, V> implements Iterable<Grouping<K, V>> 

Constructors

constructor(entries, keyEqualer)

Creates a new Lookup for the provided groups.

Declaration

constructor(entries: Iterable<[K, Iterable<V>]>, keyEqualer?: Equaler<K>);

Parameters

entries

Iterable<[K, Iterable<V>]>

A map containing the unique groups of values.

keyEqualer

Equaler<K>

Properties

size

Gets the number of unique keys.

Declaration

get size(): number;

Property Value

number

Methods

[Symbol.iterator]()

Declaration

[Symbol.iterator](): Iterator<Grouping<K, V>, any, undefined>;

Returns

Iterator<Grouping<K, V>, any, undefined>

applyResultSelector(selector)

Creates a Query that maps each group in the Lookup.

Declaration

applyResultSelector<R>(selector: (key: K, elements: Iterable<V>) => R): Iterable<R>;

Type Parameters

R

Parameters

selector

(key: K, elements: Iterable<V>) => R

A callback used to select results for each group.

Returns

Iterable<R>

get(key)

Gets the group for the provided key.

Declaration

get(key: K): Iterable<V>;

Parameters

key

K

A key.

Returns

Iterable<V>

has(key)

Declaration

has(key: K): boolean;

Parameters

key

K

A key. Gets a value indicating whether any group has the provided key.

Returns

boolean