42 lines
No EOL
925 B
TypeScript
42 lines
No EOL
925 B
TypeScript
import type { Timed } from './types';
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import ListWalker from './ListWalker'
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type CheckFn<T> = (t: T) => boolean
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export default class ListWalkerWithMarks<T extends Timed> extends ListWalker<T> {
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private _markCountNow: number = 0
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private _markCount: number = 0
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constructor(private isMarked: CheckFn<T>, initialList: T[] = []) {
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super(initialList)
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this._markCount = initialList.reduce((n, item) => isMarked(item) ? n+1 : n, 0)
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}
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append(item: T) {
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if (this.isMarked(item)) { this._markCount++ }
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super.append(item)
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}
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protected moveNext() {
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const val = super.moveNext()
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if (val && this.isMarked(val)) {
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this._markCountNow++
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}
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return val
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}
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protected movePrev() {
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const val = super.movePrev()
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if (val && this.isMarked(val)) {
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this._markCountNow--
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}
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return val
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}
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get markedCountNow(): number {
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return this._markCountNow
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}
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get markedCount(): number {
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return this._markCount
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}
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} |