json-map.js

'use strict'

class JSONMap extends Map {
  constructor (value) {
    let mapArgs = []
    if (value) {
      for (let k of Object.keys(value)) {
        mapArgs.push([ k, value[k] ])
      }
    }
    super(mapArgs)
  }

  get (key, defaultValue) {
    const value = super.get(key)
    if (value === undefined && defaultValue !== undefined) {
      return defaultValue
    }
    return value
  }

  toJSON () {
    const obj = Object.create(null)
    for (let [k, v] of this.entries()) {
      if (v instanceof JSONMap) {
        obj[k] = v.toJSON()
      } else {
        obj[k] = v
      }
    }
    return obj
  }
}

exports.JSONMap = JSONMap

exports.createJSONMap = value => new JSONMap(value)