giantdb/dist/idset.js

Large object database in native JavaScript, with encryption support

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.IdSet = void 0;
/**
 * A set of string ids, which can be lazy-loaded and iterated over.
 */
class IdSet {
    _backingSet;
    _getBackingSet;
    /**
     * Construct a new IdSet. The load function is used to obtain the initial list
     * of ids.
     *
     * @param loadFunction A function returning or promising an array of strings, the initial ids.
     */
    constructor(loadFunction) {
        // private method that promises the backing set on which to operate
        this._getBackingSet = async () => {
            if (this._backingSet == null) {
                this._backingSet = new Set(await loadFunction());
            }
            return this._backingSet;
        };
    }
    /**
     * Add the given id to the set.
     *
     * @param id The id to add.
     * @returns A Promise that is resolved when done.
     */
    async add(id) {
        const set = await this._getBackingSet();
        set.add(id);
    }
    /**
     * Remove the given id from the set.
     *
     * @param id The id to remove.
     * @returns A Promise that is resolved when done.
     */
    async remove(id) {
        const set = await this._getBackingSet();
        set.delete(id);
    }
    /**
     * Determine whether the given id is contained in this set.
     *
     * @param id The id to check.
     * @returns A Promise for whether the id is in this set.
     */
    async includes(id) {
        const set = await this._getBackingSet();
        return set.has(id);
    }
    /**
     * Iterate over all ids in this set. Iteration happens sequentially. If the
     * callback returns a Promise or thenable, it is awaited before continuing with
     * the next element.
     *
     * @param callbackFn The function to execute for each set element.
     * @returns A Promise that is resolved when iteration is finished.
     */
    async each(callbackFn) {
        const set = await this._getBackingSet();
        for (const value of set) {
            await callbackFn(value);
        }
    }
}
exports.IdSet = IdSet;