@esfx/indexed-object Package

Provides a base class for custom integer-indexed collections.

The underlying implementation uses a Proxy to trap integer indexes in a fashion similar to the Integer-Indexed Exotic Object in the ECMAScript specification.

Installation

npm i @esfx/indexed-object

Usage

TypeScript
JavaScript (CommonJS)

import { IntegerIndexedObject } from "@esfx/indexed-object";

class BooleansCollection extends IntegerIndexedObject<boolean> {
    protected getLength() {
        return 2;
    }
    protected getIndex(index: number) {
        switch (index) {
            case 0: return false;
            case 1: return true;
            default: return undefined;
        }
    }
    // hasIndex(index): boolean
    // setIndex(index, value): boolean
    // deleteIndex(index): boolean
}

const booleans = new BooleansCollection();
console.log(booleans[0]); // false
console.log(booleans[1]); // true

const { IntegerIndexedObject } = require("@esfx/indexed-object");

class BooleansCollection extends IntegerIndexedObject {
    /** @protected */
    getLength() {
        return 2;
    }
    /** @protected */
    getIndex(index) {
        switch (index) {
            case 0: return false;
            case 1: return true;
            default: return undefined;
        }
    }
    // hasIndex(index): boolean
    // setIndex(index, value): boolean
    // deleteIndex(index): boolean
}

const booleans = new BooleansCollection();
console.log(booleans[0]); // false
console.log(booleans[1]); // true

Classes

IntegerIndexedObject

Represents an object that can be indexed by an integer value similar to a native Array or TypedArray.