LinkedHashMap

data-structure-typed

---

data-structure-typed / LinkedHashMap

Class: LinkedHashMap<K, V, R>

Defined in: data-structures/hash/hash-map.ts:523

Hash-based map that preserves insertion order via a doubly-linked list.

Remarks

Time O(1), Space O(1)

Example

examples will be generated by unit test

Extends

• IterableEntryBase<K, V>

Type Parameters

K

K = any

V

V = any

R

R = [K, V]

Constructors

Constructor

new LinkedHashMap<K, V, R>(entryOrRawElements?, options?): LinkedHashMap<K, V, R>;

Defined in: data-structures/hash/hash-map.ts:533

Create a LinkedHashMap and optionally bulk-insert entries.

Parameters

entryOrRawElements?

Iterable<[K, V] | R> = []

Iterable of entries or raw elements to insert.

options?

LinkedHashMapOptions<K, V, R>

Options: hash functions and optional record-to-entry converter.

Returns

LinkedHashMap<K, V, R>

New LinkedHashMap instance.

Remarks

Time O(N), Space O(N)

Overrides

IterableEntryBase<K, V>.constructor

Accessors

first

Get Signature

get first(): [K, V] | undefined;

Defined in: data-structures/hash/hash-map.ts:615

Get the first [key, value] pair.

Remarks

Time O(1), Space O(1)

Returns

[K, V] | undefined

First entry or undefined when empty.

---

head

Get Signature

get head(): HashMapLinkedNode<K, V | undefined>;

Defined in: data-structures/hash/hash-map.ts:585

Get the head node (first entry) sentinel link.

Remarks

Time O(1), Space O(1)

Returns

HashMapLinkedNode<K, V | undefined>

Head node or sentinel.

---

last

Get Signature

get last(): [K, V] | undefined;

Defined in: data-structures/hash/hash-map.ts:625

Get the last [key, value] pair.

Remarks

Time O(1), Space O(1)

Returns

[K, V] | undefined

Last entry or undefined when empty.

---

noObjMap

Get Signature

get noObjMap(): Record<string, HashMapLinkedNode<K, V | undefined>>;

Defined in: data-structures/hash/hash-map.ts:569

Get the internal record for non-object keys.

Remarks

Time O(1), Space O(1)

Returns

Record<string, HashMapLinkedNode<K, V | undefined>>

Record of hash→node.

---

objHashFn

Get Signature

get objHashFn(): (key) => object;

Defined in: data-structures/hash/hash-map.ts:558

Get the hash function for object/weak keys.

Remarks

Time O(1), Space O(1)

Returns

Object-hash function.

(key) => object

---

size

Get Signature

get size(): number;

Defined in: data-structures/hash/hash-map.ts:606

Total number of entries.

Remarks

Time O(1), Space O(1)

Returns

number

Entry count.

Overrides

IterableEntryBase.size

---

tail

Get Signature

get tail(): HashMapLinkedNode<K, V | undefined>;

Defined in: data-structures/hash/hash-map.ts:596

Get the tail node (last entry) sentinel link.

Remarks

Time O(1), Space O(1)

Returns

HashMapLinkedNode<K, V | undefined>

Tail node or sentinel.

Methods

[iterator]()

iterator: IterableIterator<[K, V]>;

Defined in: data-structures/base/iterable-entry-base.ts:22

Default iterator yielding [key, value] entries.

Parameters

args

...unknown[]

Returns

IterableIterator<[K, V]>

Iterator of [K, V].

Remarks

Time O(n) to iterate, Space O(1)

Inherited from

IterableEntryBase.[iterator]

---

at()

at(index): V | undefined;

Defined in: data-structures/hash/hash-map.ts:740

Get the value at a given index in insertion order.

Parameters

index

number

Zero-based index.

Returns

V | undefined

Value at the index.

Remarks

Time O(N), Space O(1)

---

begin()

begin(): Generator<(K | V | undefined)[], void, unknown>;

Defined in: data-structures/hash/hash-map.ts:635

Iterate from head → tail.

Returns

Generator<(K | V | undefined)[], void, unknown>

Iterator of [key, value].

Remarks

Time O(N), Space O(1)

---

clear()

clear(): void;

Defined in: data-structures/hash/hash-map.ts:813

Remove all entries.

Returns

void

Remarks

Time O(n) typical, Space O(1)

Overrides

IterableEntryBase.clear

---

clone()

clone(): this;

Defined in: data-structures/hash/hash-map.ts:819

Deep clone preserving the concrete subtype.

Returns

this

A new instance of the same concrete class (this type).

Remarks

Time O(n) typical, Space O(n)

Overrides

IterableEntryBase.clone

---

deleteAt()

deleteAt(index): [K, V | undefined];

Defined in: data-structures/hash/hash-map.ts:796

Delete the entry at a given index.

Parameters

index

number

Zero-based index.

Returns

[K, V | undefined]

The removed entry [key, value].

Remarks

Time O(N), Space O(1)

Throws

If index is out of bounds.

---

deleteWhere()

deleteWhere(predicate): boolean;

Defined in: data-structures/hash/hash-map.ts:769

Delete the first entry that matches a predicate.

Parameters

predicate

(key, value, index, map) => boolean

Function (key, value, index, map) → boolean to decide deletion.

Returns

boolean

True if an entry was removed.

Remarks

Time O(N), Space O(1)

---

entries()

entries(): IterableIterator<[K, V | undefined]>;

Defined in: data-structures/base/iterable-entry-base.ts:31

Iterate over [key, value] pairs (may yield undefined values).

Returns

IterableIterator<[K, V | undefined]>

Iterator of [K, V | undefined].

Remarks

Time O(n), Space O(1)

Inherited from

IterableEntryBase.entries

---

every()

every(predicate, thisArg?): boolean;

Defined in: data-structures/base/iterable-entry-base.ts:66

Test whether all entries satisfy the predicate.

Parameters

predicate

EntryCallback<K, V, boolean>

(key, value, index, self) => boolean.

thisArg?

unknown

Optional this for callback.

Returns

boolean

true if all pass; otherwise false.

Remarks

Time O(n), Space O(1)

Inherited from

IterableEntryBase.every

---

filter()

filter(predicate, thisArg?): this;

Defined in: data-structures/hash/hash-map.ts:824

Filter entries and return the same-species structure.

Parameters

predicate

EntryCallback<K, V, boolean>

thisArg?

unknown

Returns

this

A new instance of the same concrete class (this type).

Remarks

Time O(n), Space O(n)

Overrides

IterableEntryBase.filter

---

find()

find(callbackfn, thisArg?): [K, V] | undefined;

Defined in: data-structures/base/iterable-entry-base.ts:114

Find the first entry that matches a predicate.

Parameters

callbackfn

EntryCallback<K, V, boolean>

(key, value, index, self) => boolean.

thisArg?

unknown

Optional this for callback.

Returns

[K, V] | undefined

Matching [key, value] or undefined.

Remarks

Time O(n), Space O(1)

Inherited from

IterableEntryBase.find

---

forEach()

forEach(callbackfn, thisArg?): void;

Defined in: data-structures/base/iterable-entry-base.ts:99

Visit each entry, left-to-right.

Parameters

callbackfn

EntryCallback<K, V, void>

(key, value, index, self) => void.

thisArg?

unknown

Optional this for callback.

Returns

void

Remarks

Time O(n), Space O(1)

Inherited from

IterableEntryBase.forEach

---

get()

get(key): V | undefined;

Defined in: data-structures/hash/hash-map.ts:723

Get the value under a key.

Parameters

key

K

Key to look up.

Returns

V | undefined

Value or undefined.

Remarks

Time O(n) generic, Space O(1)

Overrides

IterableEntryBase.get

---

has()

has(key): boolean;

Defined in: data-structures/hash/hash-map.ts:714

Whether the given key exists.

Parameters

key

K

Key to test.

Returns

boolean

true if found; otherwise false.

Remarks

Time O(n) generic, Space O(1)

Overrides

IterableEntryBase.has

---

hasValue()

hasValue(value): boolean;

Defined in: data-structures/base/iterable-entry-base.ts:143

Whether there exists an entry with the given value.

Parameters

value

V

Value to test.

Returns

boolean

true if found; otherwise false.

Remarks

Time O(n), Space O(1)

Inherited from

IterableEntryBase.hasValue

---

isEmpty()

isEmpty(): boolean;

Defined in: data-structures/hash/hash-map.ts:805

Whether there are no entries.

Returns

boolean

true if empty; false otherwise.

Remarks

Time O(1) typical, Space O(1)

Overrides

IterableEntryBase.isEmpty

---

keys()

keys(): IterableIterator<K>;

Defined in: data-structures/base/iterable-entry-base.ts:42

Iterate over keys only.

Returns

IterableIterator<K>

Iterator of keys.

Remarks

Time O(n), Space O(1)

Inherited from

IterableEntryBase.keys

---

map()

map<MK, MV>(callback, thisArg?): LinkedHashMap<MK, MV>;

Defined in: data-structures/hash/hash-map.ts:843

Map each entry to a new [key, value] pair and preserve order.

Type Parameters

MK

MK

MV

MV

Parameters

callback

EntryCallback<K, V, [MK, MV]>

Mapping function (key, value, index, map) → [newKey, newValue].

thisArg?

unknown

Value for this inside the callback.

Returns

LinkedHashMap<MK, MV>

A new map of the same class with transformed entries.

Remarks

Time O(N), Space O(N)

Overrides

IterableEntryBase.map

---

print()

print(): void;

Defined in: data-structures/base/iterable-entry-base.ts:203

Print a human-friendly representation to the console.

Returns

void

Remarks

Time O(n), Space O(n)

Inherited from

IterableEntryBase.print

---

reduce()

reduce<U>(callbackfn, initialValue): U;

Defined in: data-structures/base/iterable-entry-base.ts:171

Reduce entries into a single accumulator.

Type Parameters

U

U

Parameters

callbackfn

ReduceEntryCallback<K, V, U>

(acc, value, key, index, self) => acc.

initialValue

U

Initial accumulator.

Returns

U

Final accumulator.

Remarks

Time O(n), Space O(1)

Inherited from

IterableEntryBase.reduce

---

reverseBegin()

reverseBegin(): Generator<(K | V | undefined)[], void, unknown>;

Defined in: data-structures/hash/hash-map.ts:648

Iterate from tail → head.

Returns

Generator<(K | V | undefined)[], void, unknown>

Iterator of [key, value].

Remarks

Time O(N), Space O(1)

---

set()

set(key, value?): this;

Defined in: data-structures/hash/hash-map.ts:663

Insert or replace a single entry; preserves insertion order.

Parameters

key

K

Key.

value?

V

Value.

Returns

this

This map (for chaining).

Remarks

Time O(1), Space O(1)

---

some()

some(predicate, thisArg?): boolean;

Defined in: data-structures/base/iterable-entry-base.ts:83

Test whether any entry satisfies the predicate.

Parameters

predicate

EntryCallback<K, V, boolean>

(key, value, index, self) => boolean.

thisArg?

unknown

Optional this for callback.

Returns

boolean

true if any passes; otherwise false.

Remarks

Time O(n), Space O(1)

Inherited from

IterableEntryBase.some

---

toArray()

toArray(): [K, V][];

Defined in: data-structures/base/iterable-entry-base.ts:186

Converts data structure to [key, value] pairs.

Returns

[K, V][]

Array of entries.

Remarks

Time O(n), Space O(n)

Inherited from

IterableEntryBase.toArray

---

toVisual()

toVisual(): string | [K, V][];

Defined in: data-structures/base/iterable-entry-base.ts:195

Visualize the iterable as an array of [key, value] pairs (or a custom string).

Returns

string | [K, V][]

Array of entries (default) or a string.

Remarks

Time O(n), Space O(n)

Inherited from

IterableEntryBase.toVisual

---

values()

values(): IterableIterator<V>;

Defined in: data-structures/base/iterable-entry-base.ts:53

Iterate over values only.

Returns

IterableIterator<V>

Iterator of values.

Remarks

Time O(n), Space O(1)

Inherited from

IterableEntryBase.values

---

Protected Members

_getIterator()

protected _getIterator(): IterableIterator<[K, V]>;

Defined in: data-structures/hash/hash-map.ts:867

Underlying iterator for the default iteration protocol.

Returns

IterableIterator<[K, V]>

Iterator of [K, V].

Remarks

Time O(n), Space O(1)

Overrides

IterableEntryBase._getIterator

---