[**data-structure-typed**](../README.md) *** [data-structure-typed](../README.md) / IterableElementBase # Abstract Class: IterableElementBase\ Defined in: [data-structures/base/iterable-element-base.ts:15](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L15) Base class that makes a data structure iterable and provides common element-wise utilities (e.g., map/filter/reduce/find). ## Remarks This class implements the JavaScript iteration protocol (via `Symbol.iterator`) and offers array-like helpers with predictable time/space complexity. ## Extended by - [`Stack`](Stack.md) - [`Heap`](Heap.md) - [`Trie`](Trie.md) - [`LinearBase`](LinearBase.md) ## Type Parameters ### E `E` The public element type yielded by the structure. ### R `R` The underlying "raw" element type used internally or by converters. ## Implements - `Iterable`\<`E`\> ## Constructors ### toElementFn #### Get Signature ```ts get toElementFn(): ((rawElement) => E) | undefined; ``` Defined in: [data-structures/base/iterable-element-base.ts:48](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L48) Exposes the current `toElementFn`, if configured. ##### Remarks Time O(1), Space O(1). ##### Returns ((`rawElement`) => `E`) \| `undefined` The converter function or `undefined` when not set. ## Methods ### \[iterator\]() ```ts iterator: IterableIterator; ``` Defined in: [data-structures/base/iterable-element-base.ts:61](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L61) Returns an iterator over the structure's elements. #### Parameters ##### args ...`unknown`[] Optional iterator arguments forwarded to the internal iterator. #### Returns `IterableIterator`\<`E`\> An `IterableIterator` that yields the elements in traversal order. #### Remarks Producing the iterator is O(1); consuming the entire iterator is Time O(n) with O(1) extra space. #### Implementation of ```ts Iterable.[iterator] ``` *** ### clear() ```ts abstract clear(): void; ``` Defined in: [data-structures/base/iterable-element-base.ts:321](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L321) Removes all elements from the structure. #### Returns `void` `void`. #### Remarks Expected Time O(1) or O(n) depending on the implementation; Space O(1). *** ### clone() ```ts abstract clone(): this; ``` Defined in: [data-structures/base/iterable-element-base.ts:330](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L330) Creates a structural copy with the same element values and configuration. #### Returns `this` A clone of the current instance (same concrete type). #### Remarks Expected Time O(n) to copy elements; Space O(n). *** ### entries() ```ts entries(): IterableIterator<[number, E]>; ``` Defined in: [data-structures/base/iterable-element-base.ts:208](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L208) Return an iterator of `[index, value]` pairs (Array-compatible). #### Returns `IterableIterator`\<\[`number`, `E`\]\> #### Remarks Provided for familiarity when migrating from Array. Time O(n), Space O(1) per step. *** ### every() ```ts every(predicate, thisArg?): boolean; ``` Defined in: [data-structures/base/iterable-element-base.ts:87](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L87) Tests whether all elements satisfy the predicate. #### Parameters ##### predicate `ElementCallback`\<`E`, `R`, `boolean`\> Function invoked for each element with signature `(value, index, self)`. ##### thisArg? `unknown` Optional `this` binding for the predicate. #### Returns `boolean` `true` if every element passes; otherwise `false`. #### Remarks Time O(n) in the worst case; may exit early when the first failure is found. Space O(1). *** ### filter() ```ts abstract filter(predicate, thisArg?): this; ``` Defined in: [data-structures/base/iterable-element-base.ts:373](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L373) Filters elements using the provided predicate and returns the same concrete structure type. #### Parameters ##### predicate `ElementCallback`\<`E`, `R`, `boolean`\> Function with signature `(value, index, self) => boolean`. ##### thisArg? `unknown` Optional `this` binding for the predicate. #### Returns `this` A new instance of the same concrete type containing only elements that pass the predicate. #### Remarks Time O(n), Space O(k) where `k` is the number of kept elements. *** ### find() #### Call Signature ```ts find(predicate, thisArg?): S | undefined; ``` Defined in: [data-structures/base/iterable-element-base.ts:163](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L163) Finds the first element that satisfies the predicate and returns it. Finds the first element of type `S` (a subtype of `E`) that satisfies the predicate and returns it. ##### Type Parameters ###### S `S` ##### Parameters ###### predicate `ElementCallback`\<`E`, `R`, `S`\> Type-guard predicate: `(value, index, self) => value is S`. ###### thisArg? `unknown` Optional `this` binding for the predicate. ##### Returns `S` \| `undefined` The matched element typed as `S`, or `undefined` if not found. ##### Remarks Time O(n) in the worst case; may exit early on the first match. Space O(1). #### Call Signature ```ts find(predicate, thisArg?): E | undefined; ``` Defined in: [data-structures/base/iterable-element-base.ts:164](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L164) Finds the first element that satisfies the predicate and returns it. Finds the first element of type `S` (a subtype of `E`) that satisfies the predicate and returns it. ##### Parameters ###### predicate `ElementCallback`\<`E`, `R`, `unknown`\> Type-guard predicate: `(value, index, self) => value is S`. ###### thisArg? `unknown` Optional `this` binding for the predicate. ##### Returns `E` \| `undefined` The matched element typed as `S`, or `undefined` if not found. ##### Remarks Time O(n) in the worst case; may exit early on the first match. Space O(1). *** ### forEach() ```ts forEach(callbackfn, thisArg?): void; ``` Defined in: [data-structures/base/iterable-element-base.ts:133](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L133) Invokes a callback for each element in iteration order. #### Parameters ##### callbackfn `ElementCallback`\<`E`, `R`, `void`\> Function invoked per element with signature `(value, index, self)`. ##### thisArg? `unknown` Optional `this` binding for the callback. #### Returns `void` `void`. #### Remarks Time O(n), Space O(1). *** ### has() ```ts has(element): boolean; ``` Defined in: [data-structures/base/iterable-element-base.ts:189](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L189) Checks whether a strictly-equal element exists in the structure. #### Parameters ##### element `E` The element to test with `===` equality. #### Returns `boolean` `true` if an equal element is found; otherwise `false`. #### Remarks Time O(n) in the worst case. Space O(1). *** ### includes() ```ts includes(element): boolean; ``` Defined in: [data-structures/base/iterable-element-base.ts:200](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L200) Check whether a value exists (Array-compatible alias for `has`). #### Parameters ##### element `E` Element to search for (uses `===`). #### Returns `boolean` `true` if found. #### Remarks Provided for familiarity when migrating from Array. Time O(n), Space O(1). *** ### isEmpty() ```ts abstract isEmpty(): boolean; ``` Defined in: [data-structures/base/iterable-element-base.ts:312](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L312) Indicates whether the structure currently contains no elements. #### Returns `boolean` `true` if empty; otherwise `false`. #### Remarks Expected Time O(1), Space O(1) for most implementations. *** ### keys() ```ts keys(): IterableIterator; ``` Defined in: [data-structures/base/iterable-element-base.ts:219](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L219) Return an iterator of numeric indices (Array-compatible). #### Returns `IterableIterator`\<`number`\> #### Remarks Provided for familiarity when migrating from Array. Time O(n), Space O(1) per step. *** ### map() ```ts abstract map( callback, options?, thisArg?): IterableElementBase; ``` Defined in: [data-structures/base/iterable-element-base.ts:345](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L345) Maps each element to a new element and returns a new iterable structure. #### Type Parameters ##### EM `EM` The mapped element type. ##### RM `RM` The mapped raw element type used internally by the target structure. #### Parameters ##### callback `ElementCallback`\<`E`, `R`, `EM`\> Function with signature `(value, index, self) => mapped`. ##### options? `IterableElementBaseOptions`\<`EM`, `RM`\> Optional options for the returned structure, including its `toElementFn`. ##### thisArg? `unknown` Optional `this` binding for the callback. #### Returns `IterableElementBase`\<`EM`, `RM`\> A new `IterableElementBase` containing mapped elements. #### Remarks Time O(n), Space O(n). *** ### mapSame() ```ts abstract mapSame(callback, thisArg?): this; ``` Defined in: [data-structures/base/iterable-element-base.ts:361](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L361) Maps each element to the same element type and returns the same concrete structure type. #### Parameters ##### callback `ElementCallback`\<`E`, `R`, `E`\> Function with signature `(value, index, self) => mappedValue`. ##### thisArg? `unknown` Optional `this` binding for the callback. #### Returns `this` A new instance of the same concrete type with mapped elements. #### Remarks Time O(n), Space O(n). *** ### print() ```ts print(): void; ``` Defined in: [data-structures/base/iterable-element-base.ts:301](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L301) Prints `toVisual()` to the console. Intended for quick debugging. #### Returns `void` `void`. #### Remarks Time O(n) due to materialization, Space O(n) for the intermediate representation. *** ### reduce() Reduces all elements to a single accumulated value. #### Param Reducer of signature `(acc, value, index, self) => nextAcc`. The first element is used as the initial accumulator. #### Param Reducer of signature `(acc, value, index, self) => nextAcc`. #### Param The initial accumulator value of type `E`. #### Template The accumulator type when it differs from `E`. #### Param Reducer of signature `(acc: U, value, index, self) => U`. #### Param The initial accumulator value of type `U`. #### Remarks Time O(n), Space O(1). Throws if called on an empty structure without `initialValue`. #### Call Signature ```ts reduce(callbackfn): E; ``` Defined in: [data-structures/base/iterable-element-base.ts:226](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L226) ##### Parameters ###### callbackfn `ReduceElementCallback`\<`E`, `R`\> ##### Returns `E` #### Call Signature ```ts reduce(callbackfn, initialValue): E; ``` Defined in: [data-structures/base/iterable-element-base.ts:227](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L227) ##### Parameters ###### callbackfn `ReduceElementCallback`\<`E`, `R`\> ###### initialValue `E` ##### Returns `E` #### Call Signature ```ts reduce(callbackfn, initialValue): U; ``` Defined in: [data-structures/base/iterable-element-base.ts:228](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L228) ##### Type Parameters ###### U `U` ##### Parameters ###### callbackfn `ReduceElementCallback`\<`E`, `R`, `U`\> ###### initialValue `U` ##### Returns `U` *** ### some() ```ts some(predicate, thisArg?): boolean; ``` Defined in: [data-structures/base/iterable-element-base.ts:110](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L110) Tests whether at least one element satisfies the predicate. #### Parameters ##### predicate `ElementCallback`\<`E`, `R`, `boolean`\> Function invoked for each element with signature `(value, index, self)`. ##### thisArg? `unknown` Optional `this` binding for the predicate. #### Returns `boolean` `true` if any element passes; otherwise `false`. #### Remarks Time O(n) in the worst case; may exit early on first success. Space O(1). *** ### toArray() ```ts toArray(): E[]; ``` Defined in: [data-structures/base/iterable-element-base.ts:278](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L278) Materializes the elements into a new array. #### Returns `E`[] A shallow array copy of the iteration order. #### Remarks Time O(n), Space O(n). *** ### toVisual() ```ts toVisual(): E[]; ``` Defined in: [data-structures/base/iterable-element-base.ts:290](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L290) Returns a representation of the structure suitable for quick visualization. Defaults to an array of elements; subclasses may override to provide richer visuals. #### Returns `E`[] A visual representation (array by default). #### Remarks Time O(n), Space O(n). *** ### values() ```ts values(): IterableIterator; ``` Defined in: [data-structures/base/iterable-element-base.ts:72](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L72) Returns an iterator over the values (alias of the default iterator). #### Returns `IterableIterator`\<`E`\> An `IterableIterator` over all elements. #### Remarks Creating the iterator is O(1); full iteration is Time O(n), Space O(1). --- ## Protected Members ### Constructor ```ts protected new IterableElementBase(options?): IterableElementBase; ``` Defined in: [data-structures/base/iterable-element-base.ts:25](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L25) Create a new iterable base. #### Parameters ##### options? `IterableElementBaseOptions`\<`E`, `R`\> Optional behavior overrides. When provided, a `toElementFn` is used to convert a raw element (`R`) into a public element (`E`). #### Returns `IterableElementBase`\<`E`, `R`\> #### Remarks Time O(1), Space O(1). ## Properties ### \_toElementFn? ```ts protected optional _toElementFn?: (rawElement) => E; ``` Defined in: [data-structures/base/iterable-element-base.ts:39](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L39) The converter used to transform a raw element (`R`) into a public element (`E`). #### Parameters ##### rawElement `R` #### Returns `E` #### Remarks Time O(1), Space O(1). ## Accessors ### \_getIterator() ```ts abstract protected _getIterator(...args): IterableIterator; ``` Defined in: [data-structures/base/iterable-element-base.ts:384](https://github.com/zrwusa/data-structure-typed/blob/main/src/data-structures/base/iterable-element-base.ts#L384) Internal iterator factory used by the default iterator. #### Parameters ##### args ...`unknown`[] Optional iterator arguments. #### Returns `IterableIterator`\<`E`\> An iterator over elements. #### Remarks Implementations should yield in O(1) per element with O(1) extra space when possible. ***