mathjs/lib/expression/node/utils/access.js

Math.js is an extensive math library for JavaScript and Node.js. It features a flexible expression parser with support for symbolic computation, comes with a large set of built-in functions and constants, and offers an integrated solution to work with dif

'use strict';

function _typeof(obj) { if (typeof Symbol === "function" && typeof Symbol.iterator === "symbol") { _typeof = function _typeof(obj) { return typeof obj; }; } else { _typeof = function _typeof(obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; }; } return _typeof(obj); }

var errorTransform = require('../../transform/error.transform').transform;

var getSafeProperty = require('../../../utils/customs').getSafeProperty;

function factory(type, config, load, typed) {
  var subset = load(require('../../../function/matrix/subset'));
  /**
   * Retrieve part of an object:
   *
   * - Retrieve a property from an object
   * - Retrieve a part of a string
   * - Retrieve a matrix subset
   *
   * @param {Object | Array | Matrix | string} object
   * @param {Index} index
   * @return {Object | Array | Matrix | string} Returns the subset
   */

  return function access(object, index) {
    try {
      if (Array.isArray(object)) {
        return subset(object, index);
      } else if (object && typeof object.subset === 'function') {
        // Matrix
        return object.subset(index);
      } else if (typeof object === 'string') {
        // TODO: move getStringSubset into a separate util file, use that
        return subset(object, index);
      } else if (_typeof(object) === 'object') {
        if (!index.isObjectProperty()) {
          throw new TypeError('Cannot apply a numeric index as object property');
        }

        return getSafeProperty(object, index.getObjectProperty());
      } else {
        throw new TypeError('Cannot apply index: unsupported type of object');
      }
    } catch (err) {
      throw errorTransform(err);
    }
  };
}

exports.factory = factory;