https://github.com/printercu/coffee_classkit

Enhance coffeescript inheritance model! With an eye on ruby classes & modules.
https://github.com/printercu/coffee_classkit

Last synced: 27 days ago
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Enhance coffeescript inheritance model! With an eye on ruby classes & modules.

• Host: GitHub
• URL: https://github.com/printercu/coffee_classkit
• Owner: printercu
• License: other
• Created: 2013-04-28T10:28:40.000Z (over 11 years ago)
• Default Branch: master
• Last Pushed: 2014-01-08T14:19:28.000Z (almost 11 years ago)
• Last Synced: 2024-09-13T02:49:56.743Z (about 2 months ago)
• Language: CoffeeScript
• Homepage:
• Size: 343 KB
• Stars: 10
• Watchers: 3
• Forks: 1
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
# CoffeeClasskit

You can make much more with CoffeeScript classes.

```

npm install coffee_classkit

```

```coffee

classkit = require 'coffee_classkit'

class Child extends Parent

  classkit.extendsWithProto @

# ###

class Mixin extends classkit.Module

  @extendsWithProto().concern()

  @includedBlock: ->

    # will run in context of base class

    @instanceVariable 'test'

  class @ClassMethods

    someClassMethod: ->

  someInstanceMethod: ->

class Base extends classkit.Module

  @extendsWithProto().include Mixin

  @someClassMethod()

(new Base).someInstanceMethod()

```

## Why

`class ... extends ...` is implemented in coffee with

```coffee

for key of parent

  child[key] = parent[key]  if __hasProp_.call(parent, key)

```

It makes inheritance sticky.

* If you modify parent's property it would not be modified in child.

* Properties defined with `Object.defineProperty` would not be inherited.

* ...

## Solution

Use prototype chain for inheritance of class methods.

With `classkit.extendsWithProp @` default inheritance is redefined using

`child.__proto__ = parent`.

Ensure that you call this method before any class properties declarations,

'cause it'll drop'em all.

Once you use `extendsWithProto` you should use it on all descendents.

## Features

* It doesn't break into global namespace.

* Works on a top of usual coffee-script class declaration.

* Classes use prototypes chain.

* Full callbacks stack of Ruby-like inheritance model (`included`,

  `append_features`, `extend_object`, etc).

* Helpers to define ruby-like instance & class variables.

* `ActiveSupport::Concern`-like behaviour is optional.

* It works only 'cause of `__proto__`. Some say it's deprecated :)

## For pure JS

`Classkit.inherit` method provides inheritance that can be used in pure JS:

```js

function Parent() { /* ... */ }

var Child;

Classkit.inherit(Parent, Child = function Child(){ /* ... */ });

```

It uses CoffeeScript's inheritance. Take a look on compiled coffee source

to know how to use `super` properly.

## More examples

See source, tests & [costa](https://github.com/printercu/costa).

## License

BSD