ref: 8b6e0f7c019f532841af40b950c4048422232234 taliaferro/node_modules/is-extendable/README.md -rw-r--r-- 2.5 KiB
8b6e0f7c — Nate rebuilding site Sun Feb 9 13:47:19 CST 2020: Fix navbar symbols showing up first. 1 year, 11 months ago

#is-extendable NPM version

Returns true if a value is any of the object types: array, regexp, plain object, function or date. This is useful for determining if a value can be extended, e.g. "can the value have keys?"


Install with npm

$ npm i is-extendable --save


var isExtendable = require('is-extendable');

Returns true if the value is any of the following:

  • array
  • regexp
  • plain object
  • function
  • date
  • error


All objects in JavaScript can have keys, but it's a pain to check for this, since we ether need to verify that the value is not null or undefined and:

  • the value is not a primitive, or
  • that the object is an object, function

Also note that an extendable object is not the same as an extensible object, which is one that (in es6) is not sealed, frozen, or marked as non-extensible using preventExtensions.

  • assign-deep: Deeply assign the enumerable properties of source objects to a destination object.
  • extend-shallow: Extend an object with the properties of additional objects. node.js/javascript util.
  • isobject: Returns true if the value is an object and not an array or null.
  • is-plain-object: Returns true if an object was created by the Object constructor.
  • is-equal-shallow: Does a shallow comparison of two objects, returning false if the keys or values differ.
  • kind-of: Get the native type of a value.

#Running tests

Install dev dependencies:

$ npm i -d && npm test


Pull requests and stars are always welcome. For bugs and feature requests, please create an issue


Jon Schlinkert


Copyright © 2015 Jon Schlinkert Released under the MIT license.

This file was generated by verb-cli on July 04, 2015.