object-as-dictionary

Use of JS objects as dictionaries is common but error prone problem given the hazards of inherited properties and mutable __proto__. There for it's typically better to use objects created like Object.create(null) for dictionaries. But then when you also have entries for the dict you wind up with Object.assign(Object.create(null), {x: 1, y: 2}) finally if you type check your js code boilerplate even greater.

This is miniature library deal with this boilerplate for you:

import dictionary from 'dictionary'

const ages = dictionary({
  Tom: 32,
  Jane: 28
})

Object.getPrototypeOf(ages) // => null
'__proto__' in ages // => false
ages.__proto__ // => undefined
'constructor' in ages // => false
ages.constructor // => undefined

And if you happen to type check your JS code with flow you can take further advantage of this library:

/* @flow */
import type {Dictionary} from 'dictionary'
import dictionary from 'dictionary'


const ages:Dictionary<number> = dictionary({
  Tom: 32,
  Jane: 28
})
ages.Kate = 'two'

// flow check
//
// src/index.js:10
// 10: ages.Kate = 'two'
//                 ^^^^^ string. This type is incompatible with
// 6:  const ages:Dictionary<number> = dictionary({
//                           ^^^^^^ number