Class RcList<T>

a specialized list that keeps track of the number of duplicates of each item in the list, similar to a reference counter.

this class automatically updates the reference counter on any mutations to the list at O(log(n)), where n is the number of unique items.
note that you must use the set method for index-based assignment, otherwise the class will not be able track the changes made.

don't do: my_list[index] = "hello"
do: my_list.set(index, "hello")

Example

class TrackedList<T> extends RcList<T> {
	public onAdded(item: T): void {
		console.log(`new item introduced: ${item}`)
	}

	public onDeleted(item: T): void {
		console.log(`item completely removed: ${item}`)
	}
}

const list = new TrackedList<number>()
list.push(1, 2, 2, 3)
// logs: "new item introduced: 1", "new item introduced: 2", "new item introduced: 3"

list.pop() // removes 3
// logs: "item completely removed: 3"

list.splice(0, 1) // removes 1
// logs: "item completely removed: 1"

list.unshift(4, 4, 5)
// logs: "new item introduced: 4", "new item introduced: 5"

list.shift() // removes 4
// logs: "item completely removed: 4"

list.set(0, 6) // replaces 2 with 6
// logs: "item completely removed: 2", "new item introduced: 6"

list.set(99, 9999) // `list[99] = 9999`, in addition to extending the length of the list to `100`
// logs: "new item introduced: 99"
// the reference counter of `undefined` is now `95`, because the length of the list was extended by `96` elements,
// and the final element (index `99`) was assigned the value of `9999`.
// note that `onAdded` is not called for `undefined` elements that are introduced as a consequence of the list extending after assignment.
// but `onAdded` will be called when the user _actually_ inserts an `undefined` element via direct mutation methods.

Type Parameters

Hierarchy (view full)

List<T>
- RcList

Constructors

constructor

new RcList<T>(...args): RcList<T>
Type Parameters
- T
Parameters
- Rest...args: T[]
Returns RcList<T>
Overrides List.constructor
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:179

Properties

`Readonly`[unscopables]

[unscopables]: {
    find?: any;
    findIndex?: any;
    fill?: any;
    copyWithin?: any;
    [iterator]?: any;
    entries?: any;
    keys?: any;
    values?: any;
    [unscopables]?: boolean;
    includes?: any;
    flatMap?: any;
    flat?: any;
    at?: any;
    findLast?: any;
    findLastIndex?: any;
    toReversed?: any;
    toSorted?: any;
    toSpliced?: any;
    with?: any;
    length?: boolean;
    toString?: any;
    toLocaleString?: any;
    pop?: any;
    push?: any;
    concat?: any;
    join?: any;
    reverse?: any;
    shift?: any;
    slice?: any;
    sort?: any;
    splice?: any;
    unshift?: any;
    indexOf?: any;
    lastIndexOf?: any;
    every?: any;
    some?: any;
    forEach?: any;
    map?: any;
    filter?: any;
    reduce?: any;
    reduceRight?: any;
}

Is an object whose properties have the value 'true' when they will be absent when used in a 'with' statement.

Type declaration

Optional Readonly[unscopables]?: boolean
Is an object whose properties have the value 'true' when they will be absent when used in a 'with' statement.
Optionallength?: boolean
Gets or sets the length of the array. This is a number one higher than the highest index in the array.

`Static` `Readonly`[species]

[species]: ArrayConstructor

length

length: number

Gets or sets the length of the array. This is a number one higher than the highest index in the array.

`Protected` `Readonly`rc

rc: Map<T, number> = ...

the reference counting Map, that bookkeeps the multiplicity of each item in the list.

`Readonly`getRc

getRc: ((...args: [key: T]) => undefined | number) = ...

get the reference count (multiplicity) of a specific item in the list.

`Protected` `Readonly`setRc

setRc: ((...args: [key: T, value: number]) => Map<T, number>) = ...

set the reference count of a specific item in the list.

`Protected` `Readonly`delRc

delRc: ((...args: [key: T]) => boolean) = ...

delete the reference counting of a specific item in the list. a true is returned if the item did exist in rc, prior to deletion.

`Static`from

from: (<T, U>(arrayLike: ArrayLike<T>, mapfn?: ((v: T, k: number) => U), thisArg?: any) => RcList)

`Static`of

of: (<T>(...items: T[]) => RcList<T>)

Methods

find

find<S>(predicate, thisArg?): undefined | S
Returns the value of the first element in the array where predicate is true, and undefined otherwise.
Type Parameters
- S
Parameters
- predicate: ((value: T, index: number, obj: T[]) => value is S)
  find calls predicate once for each element of the array, in ascending order, until it finds one where predicate returns true. If such an element is found, find immediately returns that element value. Otherwise, find returns undefined.
  - - (value, index, obj): value is S
    - Parameters
      value: T
      index: number
      obj: T[]
      Returns value is S
- OptionalthisArg: any
  If provided, it will be used as the this value for each invocation of predicate. If it is not provided, undefined is used instead.
Returns undefined | S
Inherited from List.find
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2015.core.d.ts:29
find(predicate, thisArg?): undefined | T
Parameters
- predicate: ((value: T, index: number, obj: T[]) => unknown)
  - - (value, index, obj): unknown
    - Parameters
      value: T
      index: number
      obj: T[]
      Returns unknown
- OptionalthisArg: any
Returns undefined | T
Inherited from List.find
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2015.core.d.ts:30

findIndex

findIndex(predicate, thisArg?): number
Returns the index of the first element in the array where predicate is true, and -1 otherwise.
Parameters
- predicate: ((value: T, index: number, obj: T[]) => unknown)
  find calls predicate once for each element of the array, in ascending order, until it finds one where predicate returns true. If such an element is found, findIndex immediately returns that element index. Otherwise, findIndex returns -1.
  - - (value, index, obj): unknown
    - Parameters
      value: T
      index: number
      obj: T[]
      Returns unknown
- OptionalthisArg: any
  If provided, it will be used as the this value for each invocation of predicate. If it is not provided, undefined is used instead.
Returns number
Inherited from List.findIndex
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2015.core.d.ts:41

fill

fill(value, start?, end?): this
Changes all array elements from start to end index to a static value and returns the modified array
Parameters
- value: T
  value to fill array section with
- Optionalstart: number
  index to start filling the array at. If start is negative, it is treated as length+start where length is the length of the array.
- Optionalend: number
  index to stop filling the array at. If end is negative, it is treated as length+end.
Returns this
Inherited from List.fill
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2015.core.d.ts:51

copyWithin

copyWithin(target, start, end?): this
Returns the this object after copying a section of the array identified by start and end to the same array starting at position target
Parameters
- target: number
  If target is negative, it is treated as length+target where length is the length of the array.
- start: number
  If start is negative, it is treated as length+start. If end is negative, it is treated as length+end.
- Optionalend: number
  If not specified, length of the this object is used as its default value.
Returns this
Inherited from List.copyWithin
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2015.core.d.ts:62

[iterator]

[iterator](): ArrayIterator<T>
Iterator

Returns ArrayIterator<T>
Inherited from List.[iterator]
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2015.iterable.d.ts:78

entries

entries(): ArrayIterator<[number, T]>
Returns an iterable of key, value pairs for every entry in the array

Returns ArrayIterator<[number, T]>
Inherited from List.entries
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2015.iterable.d.ts:83

keys

keys(): ArrayIterator<number>
Returns an iterable of keys in the array

Returns ArrayIterator<number>
Inherited from List.keys
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2015.iterable.d.ts:88

values

values(): ArrayIterator<T>
Returns an iterable of values in the array

Returns ArrayIterator<T>
Inherited from List.values
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2015.iterable.d.ts:93

includes

includes(searchElement, fromIndex?): boolean
Determines whether an array includes a certain element, returning true or false as appropriate.
Parameters
- searchElement: T
  The element to search for.
- OptionalfromIndex: number
  The position in this array at which to begin searching for searchElement.
Returns boolean
Inherited from List.includes
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2016.array.include.d.ts:25

flat

flat<A, D>(this, depth?): FlatArray<A, D>[]
Returns a new array with all sub-array elements concatenated into it recursively up to the specified depth.
Type Parameters
- A
- D extends number = 1
Parameters
- this: A
- Optionaldepth: D
 The maximum recursion depth
Returns FlatArray<A, D>[]
Inherited from List.flat
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2019.array.d.ts:75

at

at(index): undefined | T
Returns the item located at the specified index.
Parameters
- index: number
  The zero-based index of the desired code unit. A negative index will count back from the last item.
Returns undefined | T
Inherited from List.at
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2022.array.d.ts:24

findLast

findLast<S>(predicate, thisArg?): undefined | S
Returns the value of the last element in the array where predicate is true, and undefined otherwise.
Type Parameters
- S
Parameters
- predicate: ((value: T, index: number, array: T[]) => value is S)
  findLast calls predicate once for each element of the array, in descending order, until it finds one where predicate returns true. If such an element is found, findLast immediately returns that element value. Otherwise, findLast returns undefined.
  - - (value, index, array): value is S
    - Parameters
      value: T
      index: number
      array: T[]
      Returns value is S
- OptionalthisArg: any
  If provided, it will be used as the this value for each invocation of predicate. If it is not provided, undefined is used instead.
Returns undefined | S
Inherited from List.findLast
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2023.array.d.ts:29
findLast(predicate, thisArg?): undefined | T
Parameters
- predicate: ((value: T, index: number, array: T[]) => unknown)
  - - (value, index, array): unknown
    - Parameters
      value: T
      index: number
      array: T[]
      Returns unknown
- OptionalthisArg: any
Returns undefined | T
Inherited from List.findLast
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2023.array.d.ts:30

findLastIndex

findLastIndex(predicate, thisArg?): number
Returns the index of the last element in the array where predicate is true, and -1 otherwise.
Parameters
- predicate: ((value: T, index: number, array: T[]) => unknown)
  findLastIndex calls predicate once for each element of the array, in descending order, until it finds one where predicate returns true. If such an element is found, findLastIndex immediately returns that element index. Otherwise, findLastIndex returns -1.
  - - (value, index, array): unknown
    - Parameters
      value: T
      index: number
      array: T[]
      Returns unknown
- OptionalthisArg: any
  If provided, it will be used as the this value for each invocation of predicate. If it is not provided, undefined is used instead.
Returns number
Inherited from List.findLastIndex
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2023.array.d.ts:41

toReversed

toReversed(): T[]
Returns a copy of an array with its elements reversed.

Returns T[]
Inherited from List.toReversed
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2023.array.d.ts:46

toSorted

toSorted(compareFn?): T[]
Returns a copy of an array with its elements sorted.
Parameters
- OptionalcompareFn: ((a: T, b: T) => number)
  Function used to determine the order of the elements. It is expected to return a negative value if the first argument is less than the second argument, zero if they're equal, and a positive value otherwise. If omitted, the elements are sorted in ascending, ASCII character order.
```
[11, 2, 22, 1].toSorted((a, b) => a - b) // [1, 2, 11, 22]
```
  - - (a, b): number
    - Parameters
      a: T
      b: T
      Returns number
Returns T[]
Inherited from List.toSorted
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2023.array.d.ts:57

toSpliced

toSpliced(start, deleteCount, ...items): T[]
Copies an array and removes elements and, if necessary, inserts new elements in their place. Returns the copied array.
Parameters
- start: number
  The zero-based location in the array from which to start removing elements.
- deleteCount: number
  The number of elements to remove.
- Rest...items: T[]
  Elements to insert into the copied array in place of the deleted elements.
Returns T[]
The copied array.
Inherited from List.toSpliced
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2023.array.d.ts:66
toSpliced(start, deleteCount?): T[]
Copies an array and removes elements while returning the remaining elements.
Parameters
- start: number
  The zero-based location in the array from which to start removing elements.
- OptionaldeleteCount: number
  The number of elements to remove.
Returns T[]
A copy of the original array with the remaining elements.
Inherited from List.toSpliced
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2023.array.d.ts:74

with

with(index, value): T[]
Copies an array, then overwrites the value at the provided index with the given value. If the index is negative, then it replaces from the end of the array.
Parameters
- index: number
  The index of the value to overwrite. If the index is negative, then it replaces from the end of the array.
- value: T
  The value to write into the copied array.
Returns T[]
The copied array with the updated value.
Inherited from List.with
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2023.array.d.ts:85

toString

toString(): string
Returns a string representation of an array.

Returns string
Inherited from List.toString
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1330

toLocaleString

toLocaleString(): string
Returns a string representation of an array. The elements are converted to string using their toLocaleString methods.

Returns string
Inherited from List.toLocaleString
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1334
toLocaleString(locales, options?): string
Parameters
- locales: string | string[]
- Optionaloptions: NumberFormatOptions & DateTimeFormatOptions
Returns string
Inherited from List.toLocaleString
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es2015.core.d.ts:64

concat

concat(...items): T[]
Combines two or more arrays. This method returns a new array without modifying any existing arrays.
Parameters
- Rest...items: ConcatArray<T>[]
 Additional arrays and/or items to add to the end of the array.
Returns T[]
Inherited from List.concat
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1350
concat(...items): T[]
Combines two or more arrays. This method returns a new array without modifying any existing arrays.
Parameters
- Rest...items: (T | ConcatArray<T>)[]
 Additional arrays and/or items to add to the end of the array.
Returns T[]
Inherited from List.concat
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1356

join

join(separator?): string
Adds all the elements of an array into a string, separated by the specified separator string.
Parameters
- Optionalseparator: string
  A string used to separate one element of the array from the next in the resulting string. If omitted, the array elements are separated with a comma.
Returns string
Inherited from List.join
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1361

reverse

reverse(): T[]
Reverses the elements in an array in place. This method mutates the array and returns a reference to the same array.

Returns T[]
Inherited from List.reverse
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1366

slice

slice(start?, end?): T[]
Returns a copy of a section of an array. For both start and end, a negative index can be used to indicate an offset from the end of the array. For example, -2 refers to the second to last element of the array.
Parameters
- Optionalstart: number
  The beginning index of the specified portion of the array. If start is undefined, then the slice begins at index 0.
- Optionalend: number
  The end index of the specified portion of the array. This is exclusive of the element at the index 'end'. If end is undefined, then the slice extends to the end of the array.
Returns T[]
Inherited from List.slice
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1381

sort

sort(compareFn?): this
Sorts an array in place. This method mutates the array and returns a reference to the same array.
Parameters
- OptionalcompareFn: ((a: T, b: T) => number)
  Function used to determine the order of the elements. It is expected to return a negative value if the first argument is less than the second argument, zero if they're equal, and a positive value otherwise. If omitted, the elements are sorted in ascending, ASCII character order.
```
[11,2,22,1].sort((a, b) => a - b)
```
  - - (a, b): number
    - Parameters
      a: T
      b: T
      Returns number
Returns this
Inherited from List.sort
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1392

indexOf

indexOf(searchElement, fromIndex?): number
Returns the index of the first occurrence of a value in an array, or -1 if it is not present.
Parameters
- searchElement: T
  The value to locate in the array.
- OptionalfromIndex: number
  The array index at which to begin the search. If fromIndex is omitted, the search starts at index 0.
Returns number
Inherited from List.indexOf
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1418

lastIndexOf

lastIndexOf(searchElement, fromIndex?): number
Returns the index of the last occurrence of a specified value in an array, or -1 if it is not present.
Parameters
- searchElement: T
  The value to locate in the array.
- OptionalfromIndex: number
  The array index at which to begin searching backward. If fromIndex is omitted, the search starts at the last index in the array.
Returns number
Inherited from List.lastIndexOf
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1424

every

every<S>(predicate, thisArg?): this is S[]
Determines whether all the members of an array satisfy the specified test.
Type Parameters
- S
Parameters
- predicate: ((value: T, index: number, array: T[]) => value is S)
  A function that accepts up to three arguments. The every method calls the predicate function for each element in the array until the predicate returns a value which is coercible to the Boolean value false, or until the end of the array.
  - - (value, index, array): value is S
    - Parameters
      value: T
      index: number
      array: T[]
      Returns value is S
- OptionalthisArg: any
  An object to which the this keyword can refer in the predicate function. If thisArg is omitted, undefined is used as the this value.
Returns this is S[]
Inherited from List.every
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1433
every(predicate, thisArg?): boolean
Determines whether all the members of an array satisfy the specified test.
Parameters
- predicate: ((value: T, index: number, array: T[]) => unknown)
  A function that accepts up to three arguments. The every method calls the predicate function for each element in the array until the predicate returns a value which is coercible to the Boolean value false, or until the end of the array.
  - - (value, index, array): unknown
    - Parameters
      value: T
      index: number
      array: T[]
      Returns unknown
- OptionalthisArg: any
  An object to which the this keyword can refer in the predicate function. If thisArg is omitted, undefined is used as the this value.
Returns boolean
Inherited from List.every
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1442

some

some(predicate, thisArg?): boolean
Determines whether the specified callback function returns true for any element of an array.
Parameters
- predicate: ((value: T, index: number, array: T[]) => unknown)
  A function that accepts up to three arguments. The some method calls the predicate function for each element in the array until the predicate returns a value which is coercible to the Boolean value true, or until the end of the array.
  - - (value, index, array): unknown
    - Parameters
      value: T
      index: number
      array: T[]
      Returns unknown
- OptionalthisArg: any
  An object to which the this keyword can refer in the predicate function. If thisArg is omitted, undefined is used as the this value.
Returns boolean
Inherited from List.some
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1451

forEach

forEach(callbackfn, thisArg?): void
Performs the specified action for each element in an array.
Parameters
- callbackfn: ((value: T, index: number, array: T[]) => void)
  A function that accepts up to three arguments. forEach calls the callbackfn function one time for each element in the array.
  - - (value, index, array): void
    - Parameters
      value: T
      index: number
      array: T[]
      Returns void
- OptionalthisArg: any
  An object to which the this keyword can refer in the callbackfn function. If thisArg is omitted, undefined is used as the this value.
Returns void
Inherited from List.forEach
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1457

filter

filter<S>(predicate, thisArg?): S[]
Returns the elements of an array that meet the condition specified in a callback function.
Type Parameters
- S
Parameters
- predicate: ((value: T, index: number, array: T[]) => value is S)
  A function that accepts up to three arguments. The filter method calls the predicate function one time for each element in the array.
  - - (value, index, array): value is S
    - Parameters
      value: T
      index: number
      array: T[]
      Returns value is S
- OptionalthisArg: any
  An object to which the this keyword can refer in the predicate function. If thisArg is omitted, undefined is used as the this value.
Returns S[]
Inherited from List.filter
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1469
filter(predicate, thisArg?): T[]
Returns the elements of an array that meet the condition specified in a callback function.
Parameters
- predicate: ((value: T, index: number, array: T[]) => unknown)
  A function that accepts up to three arguments. The filter method calls the predicate function one time for each element in the array.
  - - (value, index, array): unknown
    - Parameters
      value: T
      index: number
      array: T[]
      Returns unknown
- OptionalthisArg: any
  An object to which the this keyword can refer in the predicate function. If thisArg is omitted, undefined is used as the this value.
Returns T[]
Inherited from List.filter
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1475

reduce

reduce(callbackfn): T
Calls the specified callback function for all the elements in an array. The return value of the callback function is the accumulated result, and is provided as an argument in the next call to the callback function.
Parameters
- callbackfn: ((previousValue: T, currentValue: T, currentIndex: number, array: T[]) => T)
  A function that accepts up to four arguments. The reduce method calls the callbackfn function one time for each element in the array.
  - - (previousValue, currentValue, currentIndex, array): T
    - Parameters
      previousValue: T
      currentValue: T
      currentIndex: number
      array: T[]
      Returns T
Returns T
Inherited from List.reduce
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1481
reduce(callbackfn, initialValue): T
Parameters
- callbackfn: ((previousValue: T, currentValue: T, currentIndex: number, array: T[]) => T)
  - - (previousValue, currentValue, currentIndex, array): T
    - Parameters
      previousValue: T
      currentValue: T
      currentIndex: number
      array: T[]
      Returns T
- initialValue: T
Returns T
Inherited from List.reduce
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1482
reduce(callbackfn, initialValue): U
Calls the specified callback function for all the elements in an array. The return value of the callback function is the accumulated result, and is provided as an argument in the next call to the callback function.
Type Parameters
- U
Parameters
- callbackfn: ((previousValue: U, currentValue: T, currentIndex: number, array: T[]) => U)
  A function that accepts up to four arguments. The reduce method calls the callbackfn function one time for each element in the array.
  - - (previousValue, currentValue, currentIndex, array): U
    - Parameters
      previousValue: U
      currentValue: T
      currentIndex: number
      array: T[]
      Returns U
- initialValue: U
  If initialValue is specified, it is used as the initial value to start the accumulation. The first call to the callbackfn function provides this value as an argument instead of an array value.
Returns U
Inherited from List.reduce
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1488

reduceRight

reduceRight(callbackfn): T
Calls the specified callback function for all the elements in an array, in descending order. The return value of the callback function is the accumulated result, and is provided as an argument in the next call to the callback function.
Parameters
- callbackfn: ((previousValue: T, currentValue: T, currentIndex: number, array: T[]) => T)
  A function that accepts up to four arguments. The reduceRight method calls the callbackfn function one time for each element in the array.
  - - (previousValue, currentValue, currentIndex, array): T
    - Parameters
      previousValue: T
      currentValue: T
      currentIndex: number
      array: T[]
      Returns T
Returns T
Inherited from List.reduceRight
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1494
reduceRight(callbackfn, initialValue): T
Parameters
- callbackfn: ((previousValue: T, currentValue: T, currentIndex: number, array: T[]) => T)
  - - (previousValue, currentValue, currentIndex, array): T
    - Parameters
      previousValue: T
      currentValue: T
      currentIndex: number
      array: T[]
      Returns T
- initialValue: T
Returns T
Inherited from List.reduceRight
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1495
reduceRight(callbackfn, initialValue): U
Calls the specified callback function for all the elements in an array, in descending order. The return value of the callback function is the accumulated result, and is provided as an argument in the next call to the callback function.
Type Parameters
- U
Parameters
- callbackfn: ((previousValue: U, currentValue: T, currentIndex: number, array: T[]) => U)
  A function that accepts up to four arguments. The reduceRight method calls the callbackfn function one time for each element in the array.
  - - (previousValue, currentValue, currentIndex, array): U
    - Parameters
      previousValue: U
      currentValue: T
      currentIndex: number
      array: T[]
      Returns U
- initialValue: U
  If initialValue is specified, it is used as the initial value to start the accumulation. The first call to the callbackfn function provides this value as an argument instead of an array value.
Returns U
Inherited from List.reduceRight
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1501

`Static`isArray

isArray(arg): arg is any[]
Parameters
- arg: any
Returns arg is any[]
Inherited from List.isArray
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.es5.d.ts:1513

`Static`fromAsync

fromAsync<T>(iterableOrArrayLike): Promise<T[]>
Creates an array from an async iterator or iterable object.
Type Parameters
- T
Parameters
- iterableOrArrayLike: AsyncIterable<T, any, any> | Iterable<T | PromiseLike<T>, any, any> | ArrayLike<T | PromiseLike<T>>
 An async iterator or array-like object to convert to an array.
Returns Promise<T[]>
Inherited from List.fromAsync
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.esnext.array.d.ts:24
fromAsync<T, U>(iterableOrArrayLike, mapFn, thisArg?): Promise<Awaited[]>
Creates an array from an async iterator or iterable object.
Type Parameters
- T
- U
Parameters
- iterableOrArrayLike: AsyncIterable<T, any, any> | Iterable<T, any, any> | ArrayLike<T>
 An async iterator or array-like object to convert to an array.
- mapFn: ((value: Awaited<T>) => U)
 - - (value): U
 - Parameters
 value: Awaited<T>
 Returns U
- OptionalthisArg: any
 Value of 'this' used when executing mapfn.
Returns Promise<Awaited[]>
Inherited from List.fromAsync
- Defined in .cache/deno/npm/registry.npmjs.org/typescript/5.6.3/lib/lib.esnext.array.d.ts:34

insert

insert(index, item): void
inserts an item at the specified index, shifting all items ahead of it one position to the front.
negative indices are also supported for indicating the position of the newly added item after the array's length has incremented.
Parameters
- index: number
- item: T
Returns void
Example
```
const arr = new List(0, 1, 2, 3, 4)
arr.insert(-1, 5) // === [0, 1, 2, 3, 4, 5] // similar to pushing
arr.insert(-2, 4.5) // === [0, 1, 2, 3, 4, 4.5, 5]
arr.insert(1, 0.5) // === [0, 0.5, 1, 2, 3, 4, 4.5, 5]
```
Inherited from List.insert
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:43

delete

delete(index): undefined | T
deletes an item at the specified index, shifting all items ahead of it one position to the back.
negative indices are also supported for indicating the deletion index from the end of the array.
Parameters
- index: number
Returns undefined | T
Example
```
const arr = new List(0, 0.5, 1, 2, 3, 4, 4.5, 5)
arr.delete(-1) // === [0, 0.5, 1, 2, 3, 4, 4.5] // similar to popping
arr.delete(-2) // === [0, 0.5, 1, 2, 3, 4.5]
arr.delete(1) // === [0, 1, 2, 3, 4.5]
```
Inherited from List.delete
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:59

map

map(callbackfn, thisArg?): List
the map array method needs to have its signature corrected, because apparently, javascript internally creates a new instance of this, instead of a new instance of an Array. the signature of the map method in typescript is misleading, because:
- it suggests: map(callbackfn: (value: T, index: number, array: T[]) => U, thisArg?: any): U[]
- but in actuality: map(callbackfn: (value: T, index: number, array: typeof this<T>) => U, thisArg?: any): typeof this
meaning that in our case, array is of type List<T> (or a subclass thereof), and the return value is also List (or a subclass) instead of Array.
in addition, it also means that a new instance of this collection (List) is created, in order to fill it with the return output.
this is perhaps the desired behavior for many uses, but for my specific use of "reference counting" and "list-like collection of signals", this feature does not bode well, as I need to be able to account for each and every single instance. surprise instances of this class are not welcomed, since it would introduce dead dependencies in my "directed acyclic graphs" for signals.
Type Parameters
- U
Parameters
- callbackfn: ((value: T, index: number, array: RcList<T>) => U)
 - - (value, index, array): U
 - Parameters
 value: T
 index: number
 array: RcList<T>
 Returns U
- OptionalthisArg: any
Returns List
Inherited from List.map
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:83

flatMap

flatMap<U, This>(callback, thisArg?): List
see the comment on map to understand why the signature of this function needs to be corrected from the standard typescript definition.
Type Parameters
- U
- This = undefined
Parameters
- callback: ((this: This, value: T, index: number, array: RcList<T>) => U | readonly U[])
 - - (this, value, index, array): U | readonly U[]
 - Parameters
 this: This
 value: T
 index: number
 array: RcList<T>
 Returns U | readonly U[]
- OptionalthisArg: This
Returns List
Inherited from List.flatMap
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:86

mapToArray

mapToArray(callbackfn, thisArg?): U[]
see the comment on map to understand the necessity for this method, instead of the builtin array map method.
Type Parameters
- U
Parameters
- callbackfn: ((value: T, index: number, array: T[]) => U)
  - - (value, index, array): U
    - Parameters
      value: T
      index: number
      array: T[]
      Returns U
- OptionalthisArg: any
Returns U[]
Inherited from List.mapToArray
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:91

flatMapToArray

flatMapToArray(callbackfn, thisArg?): U[]
see the comment on map to understand the necessity for this method, instead of the builtin array flatMap method.
Type Parameters
- U
Parameters
- callbackfn: ((value: T, index: number, array: T[]) => U)
  - - (value, index, array): U
    - Parameters
      value: T
      index: number
      array: T[]
      Returns U
- OptionalthisArg: any
Returns U[]
Inherited from List.flatMapToArray
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:94

get

get(index): undefined | T
get an item at the specified index.
this is equivalent to using index-based getter: my_list[index].
Parameters
- index: number
Returns undefined | T
Inherited from List.get
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:99

`Protected`onAdded

onAdded(item): void
this overridable method gets called when a new unique item is determined to be added to the list.
this method is called before the item is actually added to the array, but it is executed right after its reference counter has incremented to 1.
avoid accessing or mutating the array itself in this method's body (consider it an undefined behavior).
Parameters
- item: T
  the item that is being added.
Returns void
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:190

`Protected`onDeleted

onDeleted(item): void
this overridable method gets called when a unique item (reference count of 1) is determined to be removed from the list.
this method is called before the item is actually removed from the array, but it is executed right after its reference counter has been deleted.
avoid accessing or mutating the array itself in this method's body (consider it an undefined behavior).
Parameters
- item: T
  the item that is being removed.
Returns void
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:198

`Protected`incRcs

incRcs(...items): void
increments the reference count of each item in the provided array of items.
Parameters
- Rest...items: T[]
  the items whose counts are to be incremented.
Returns void
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:204

`Protected`decRcs

decRcs(...items): void
decrements the reference count of each item in the provided array of items.
Parameters
- Rest...items: T[]
  the items whose counts are to be decremented.
Returns void
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:217

push

push(...items): number
Appends new elements to the end of an array, and returns the new length of the array.
Parameters
- Rest...items: T[]
  New elements to add to the array.
Returns number
Overrides List.push
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:230

pop

pop(): undefined | T
Removes the last element from an array and returns it. If the array is empty, undefined is returned and the array is not modified.

Returns undefined | T
Overrides List.pop
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:236

shift

shift(): undefined | T
Removes the first element from an array and returns it. If the array is empty, undefined is returned and the array is not modified.

Returns undefined | T
Overrides List.shift
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:244

unshift

unshift(...items): number
Inserts new elements at the start of an array, and returns the new length of the array.
Parameters
- Rest...items: T[]
  Elements to insert at the start of the array.
Returns number
Overrides List.unshift
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:252

splice

splice(start, deleteCount?, ...items): T[]
Removes elements from an array and, if necessary, inserts new elements in their place, returning the deleted elements.
Parameters
- start: number
  The zero-based location in the array from which to start removing elements.
- OptionaldeleteCount: number
  The number of elements to remove.
- Rest...items: T[]
Returns T[]
An array containing the elements that were deleted.
Overrides List.splice
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:258

swap

swap(index1, index2): void
swap the position of two items by their index.
if any of the two indices is out of bound, then appropriate number of empty elements will be created to fill the gap; similar to how index-based assignment works (i.e. my_list[off_bound_index] = "something" will increase my_list's length).
Parameters
- index1: number
- index2: number
Returns void
Overrides List.swap
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:265

set

set(index, value): T
sets the value at the specified index, updating the counter accordingly.
always use this method instead of index-based assignment, because the latter is not interceptable (except when using proxies):
- don't do: my_list[index] = "hello"
- do: my_list.set(index, "hello")
Parameters
- index: number
- value: T
Returns T
Overrides List.set
- Defined in work/kitchensink_ts/kitchensink_ts/src/collections.ts:279

Class RcList<T>

Example

Type Parameters

Hierarchy (view full)

Index

Constructors

Properties

Methods

Constructors

constructor

Type Parameters

Parameters

Returns RcList<T>

Properties

Readonly[unscopables]

Type declaration

Optional Readonly[unscopables]?: boolean

Optionallength?: boolean

Static Readonly[species]

length

Protected Readonlyrc

ReadonlygetRc

Protected ReadonlysetRc

Protected ReadonlydelRc

Staticfrom

Staticof

Methods

find

Type Parameters

Parameters

Parameters

Returns value is S

Returns undefined | S

Parameters

Parameters

Returns unknown

Returns undefined | T

findIndex

Parameters

Parameters

Returns unknown

Returns number

fill

Parameters

Returns this

copyWithin

Parameters

Returns this

[iterator]

Returns ArrayIterator<T>

entries

Returns ArrayIterator<[number, T]>

keys

Returns ArrayIterator<number>

values

Returns ArrayIterator<T>

includes

Parameters

Returns boolean

flat

Type Parameters

Parameters

Returns FlatArray<A, D>[]

at

Parameters

Returns undefined | T

findLast

Type Parameters

Parameters

Parameters

Returns value is S

Returns undefined | S

Parameters

Parameters

Returns unknown

Returns undefined | T

findLastIndex

Parameters

Parameters

Returns unknown

`Readonly`[unscopables]

`Optional` `Readonly`[unscopables]?: boolean

`Optional`length?: boolean

`Static` `Readonly`[species]

`Protected` `Readonly`rc

`Readonly`getRc

`Protected` `Readonly`setRc

`Protected` `Readonly`delRc

`Static`from

`Static`of