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class-utils
Advanced tools
Utils for working with JavaScript classes and prototype methods.
Install with npm:
$ npm install class-utils --save
var cu = require('class-utils');
Returns true if an array has any of the given elements, or an object has any of the give keys.
Params
obj {Object}val {String|Array}returns {Boolean}Example
cu.has(['a', 'b', 'c'], 'c');
//=> true
cu.has(['a', 'b', 'c'], ['c', 'z']);
//=> true
cu.has({a: 'b', c: 'd'}, ['c', 'z']);
//=> true
Returns true if an array or object has all of the given values.
Params
val {Object|Array}values {String|Array}returns {Boolean}Example
cu.hasAll(['a', 'b', 'c'], 'c');
//=> true
cu.hasAll(['a', 'b', 'c'], ['c', 'z']);
//=> false
cu.hasAll({a: 'b', c: 'd'}, ['c', 'z']);
//=> false
Cast the given value to an array.
Params
val {String|Array}returns {Array}Example
cu.arrayify('foo');
//=> ['foo']
cu.arrayify(['foo']);
//=> ['foo']
Returns true if a value has a contructor
Params
value {Object}returns {Boolean}Example
cu.hasConstructor({});
//=> true
cu.hasConstructor(Object.create(null));
//=> false
Get the native ownPropertyNames from the constructor of the given object. An empty array is returned if the object does not have a constructor.
Params
obj {Object}: Object that has a constructor.returns {Array}: Array of keys.Example
cu.nativeKeys({a: 'b', b: 'c', c: 'd'})
//=> ['a', 'b', 'c']
cu.nativeKeys(function(){})
//=> ['length', 'caller']
Returns property descriptor key if it's an "own" property of the given object.
Params
obj {Object}key {String}returns {Object}: Returns descriptor keyExample
function App() {}
Object.defineProperty(App.prototype, 'count', {
get: function() {
return Object.keys(this).length;
}
});
cu.getDescriptor(App.prototype, 'count');
// returns:
// {
// get: [Function],
// set: undefined,
// enumerable: false,
// configurable: false
// }
Copy a descriptor from one object to another.
Params
receiver {Object}provider {Object}name {String}returns {Object}Example
function App() {}
Object.defineProperty(App.prototype, 'count', {
get: function() {
return Object.keys(this).length;
}
});
var obj = {};
cu.copyDescriptor(obj, App.prototype, 'count');
Copy static properties, prototype properties, and descriptors from one object to another.
Params
receiver {Object}provider {Object}omit {String|Array}: One or more properties to omitreturns {Object}Inherit the static properties, prototype properties, and descriptors from of an object.
Params
receiver {Object}provider {Object}omit {String|Array}: One or more properties to omitreturns {Object}Returns a function for extending the static properties, prototype properties, and descriptors from the Parent constructor onto Child constructors.
Params
Parent {Function}: Parent ctorextend {Function}: Optional extend function to handle custom extensions. Useful when updating methods that require a specific prototype.Child {Function}: Child ctorproto {Object}: Optionally pass additional prototype properties to inherit.returns {Object}Example
var extend = cu.extend(Parent);
Parent.extend(Child);
// optional methods
Parent.extend(Child, {
foo: function() {},
bar: function() {}
});
Bubble up events emitted from static methods on the Parent ctor.
Params
Parent {Object}events {Array}: Event names to bubble upYou might also be interested in these projects:
Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.
Generate readme and API documentation with verb:
$ npm install verb && npm run docs
Or, if verb is installed globally:
$ verb
Install dev dependencies:
$ npm install -d && npm test
Jon Schlinkert
Follow me on GitHub or Twitter for updates about class-utils and my other libraries:
Copyright © 2016, Jon Schlinkert. Released under the MIT license.
This file was generated by verb, v, on April 05, 2016.
core-decorators offer decorators for classes and properties, similar to class-utils but using the decorator pattern. It provides a more modern syntax and is often preferred in environments that support decorators.
mixin-decorator is similar to class-utils in providing mixin functionalities but does so using ES7 decorators, which can be more intuitive and less verbose for developers familiar with the decorator pattern.
FAQs
Utils for working with JavaScript classes and prototype methods.
The npm package class-utils receives a total of 3,633,119 weekly downloads. As such, class-utils popularity was classified as popular.
We found that class-utils demonstrated a not healthy version release cadence and project activity because the last version was released a year ago. It has 2 open source maintainers collaborating on the project.
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