A tiny (~400 bytes gzipped) implementation of a bidirectional map in JavaScript. It can be used interchangeably with the JavaScript Map as Bimap implements its whole interface while also providing new methods. Note that Bimap requires a bijective relation between the keys and values, unlike a normal map.

Warning: Although Bimap instances are assignable to the Map ones, Bimap does NOT inherit from the Map.

Installation

Via npm:

$ npm i simple-bimap --save

Via yarn:

$ yarn add simple-bimap

Usage

import { Bimap } from "simple-bimap";

API

Apart from all the properties from the Map, the Bimap offers three extra methods:

| Method | Description | |------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | Bimap<K, V>.prototype.getByValue(value: V): K \| undefined | Returns the key associated with the given value or undefined if it doesn't exist. | | Bimap<K, V>.prototype.hasValue(value: V): boolean | Returns true if the given value is in the bimap and false otherwise. | | Bimap<K, V>.prototype.deleteByValue(value: V): boolean | Deletes a bimap entry that has a value equal to the one given as the argument. Returns true if the deletion was successful and false otherwise. |

The time complexities of each of these methods are equal to the complexities of their corresponding key-oriented counterparts (get/has/delete), so they should be sublinear.