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import { _ISelection, IValue, _IIndex, _ITable, getId, _Transaction, _Explainer, _SelectExplanation, Stats } from '../interfaces-private.ts';import { FilterBase } from './transform-base.ts';import { nullIsh } from '../utils.ts';
export class StartsWithFilter<T = any> extends FilterBase<T> {
    get index() {        return null;    }
    entropy(t: _Transaction) {        return this.onValue.index!.entropy({            type: 'ge',            key: [this.startWith],            t,        });    }
    hasItem(item: T, t: _Transaction) {        const get = this.onValue.get(item, t);        return typeof get === 'string'            && get.startsWith(this.startWith);    }
    constructor(private onValue: IValue<T>        , private startWith: string) {        super(onValue.origin!);        if (onValue.index!.expressions[0].hash !== this.onValue.hash) {            throw new Error('Startwith must be the first component of the index');        }    }

    stats(t: _Transaction): Stats | null {        return null;    }
    *enumerate(t: _Transaction): Iterable<T> {        const index = this.onValue.index!;        for (const item of index.enumerate({            type: 'ge',            key: [this.startWith],            t,        })) {            const got: string = this.onValue.get(item, t);            if (nullIsh(got) || !got.startsWith(this.startWith)) {                break;            }            yield item;        }    }
    explain(e: _Explainer): _SelectExplanation {        return {            id: e.idFor(this),            _: 'ineq',            entropy: this.entropy(e.transaction),            on: this.onValue.index!.explain(e),        };    }}