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import { IValue, _ISelection, _Transaction, _Explainer, _SelectExplanation, Stats } from '../interfaces-private.ts';import { FilterBase } from './transform-base.ts';import { Types } from '../datatypes/index.ts';
export class SeqScanFilter<T = any> extends FilterBase<T> {
    get index() {        return null;    }
    entropy(t: _Transaction) {        // boost source entropy (in case an index has the same items count)        return this.selection.entropy(t) * 1.5;    }
    hasItem(raw: T, t: _Transaction): boolean {        return !!this.getter.get(raw, t);    }
    constructor(private selection: _ISelection<T>, private getter: IValue<T>) {        super(selection);        this.getter = getter.cast(Types.bool);    }

    stats(t: _Transaction): Stats | null {        return null;    }
    *enumerate(t: _Transaction): Iterable<T> {        for (const raw of this.selection.enumerate(t)) {            const cond = this.getter.get(raw, t);            if (cond) {                yield raw;            }        }    }
    explain(e: _Explainer): _SelectExplanation {        return {            id: e.idFor(this),            _: 'seqFilter',            filtered: this.selection.explain(e),        };    }}