tui-code-snippet/object/pick.js

TOAST UI Utility: CodeSnippet

/**
 * @fileoverview Retrieve a nested item from the given object/array.
 * @author NHN FE Development Lab <dl_javascript@nhn.com>
 */

'use strict';

var isUndefined = require('../type/isUndefined');
var isNull = require('../type/isNull');

/**
 * Retrieve a nested item from the given object/array.
 * @param {object|Array} obj - Object for retrieving
 * @param {...string|number} paths - Paths of property
 * @returns {*} Value
 * @memberof module:object
 * @example
 * // ES6
 * import pick from 'tui-code-snippet/object/pick';
 * 
 * // CommonJS
 * const pick = require('tui-code-snippet/object/pick');
 *
 * cosnt obj = {
 *   'key1': 1,
 *   'nested' : {
 *     'key1': 11,
 *     'nested': {
 *       'key1': 21
 *     }
 *   }
 * };
 * pick(obj, 'nested', 'nested', 'key1'); // 21
 * pick(obj, 'nested', 'nested', 'key2'); // undefined
 *
 * const arr = ['a', 'b', 'c'];
 * pick(arr, 1); // 'b'
 */
function pick(obj, paths) { // eslint-disable-line no-unused-vars
  var args = arguments;
  var target = args[0];
  var i = 1;
  var length = args.length;

  for (; i < length; i += 1) {
    if (isUndefined(target) ||
            isNull(target)) {
      return;
    }

    target = target[args[i]];
  }

  return target; // eslint-disable-line consistent-return
}

module.exports = pick;