sherby-nested-property

A Polymer 3 mixin to add functions to obtain a nested property of an object.

Instead of using multiples && to ensure that an object have a nested value, you could use the NestedPropertyMixin to obtain the value if defined.

const data = {
  webcomponents: {
    'polymer-3': {
      npm: true,
      modules: true,
    },
    'polymer-2': {
      bower: true,
    },
  },
};

let npm;
if (data && data.webcomponents && data.webcomponents['polymer-3'] && data.webcomponents['polymer-3'].npm) {
  npm = data.webcomponents['polymer-3'].npm;
}

// eslint-disable-next-line no-console
console.log(npm);

const data = {
  webcomponents: {
    'polymer-3': {
      npm: true,
      modules: true,
    },
    'polymer-2': {
      bower: true,
    },
  },
};

const npm = this.getNestedPropertyOf(data, 'webcomponents.polymer-3.npm');

// eslint-disable-next-line no-console
console.log(npm);

Installation

As Polymer 3 use npm, you must use it to install this component:

npm install @sherby/sherby--nested-property

For the Polymer 2 version, use the SherbyElements/sherby-nested-property#^v1.0.0 inside your bower.json file.

bower install SherbyElements/sherby-nested-property --save

Use

Inmport the mixin

import { PolymerElement } from '@polymer/polymer/polymer-element.js';
import { SherbyNestedPropertyMixin } from '@sherby/sherby-nested-property/sherby-nested-property-mixin.js';

/* eslint-disable no-unused-vars */

/**
 * @customElement
 * @polymer
 * @extends {PolymerElement}
 * @appliesMixin SherbyNestedPropertyMixin
 */
class Polymer3Element extends SherbyNestedPropertyMixin(PolymerElement) {
  // Use the getNestedProperty or the getNestedPropertyOf functions
  computeData(data) {
    const npm = this.getNestedPropertyOf(data, 'webcomponents.polymer-3.npm');

    // eslint-disable-next-line no-console
    console.log(npm);
  }
}