npm package discovery and stats viewer.

Discover Tips

  • General search

    [free text search, go nuts!]

  • Package details

    pkg:[package-name]

  • User packages

    @[username]

Sponsor

Optimize Toolset

I’ve always been into building performant and accessible sites, but lately I’ve been taking it extremely seriously. So much so that I’ve been building a tool to help me optimize and monitor the sites that I build to make sure that I’m making an attempt to offer the best experience to those who visit them. If you’re into performant, accessible and SEO friendly sites, you might like it too! You can check it out at Optimize Toolset.

About

Hi, 👋, I’m Ryan Hefner  and I built this site for me, and you! The goal of this site was to provide an easy way for me to check the stats on my npm packages, both for prioritizing issues and updates, and to give me a little kick in the pants to keep up on stuff.

As I was building it, I realized that I was actually using the tool to build the tool, and figured I might as well put this out there and hopefully others will find it to be a fast and useful way to search and browse npm packages as I have.

If you’re interested in other things I’m working on, follow me on Twitter or check out the open source projects I’ve been publishing on GitHub.

I am also working on a Twitter bot for this site to tweet the most popular, newest, random packages from npm. Please follow that account now and it will start sending out packages soon–ish.

Open Software & Tools

This site wouldn’t be possible without the immense generosity and tireless efforts from the people who make contributions to the world and share their work via open source initiatives. Thank you 🙏

© 2024 – Pkg Stats / Ryan Hefner

@aboutweb/proxyclass

v2.0.6

Published

A seemless way for organizing multi inheritance.

Downloads

18

Readme

proxy-class

A seemless way to organize multi inheritance.

Caution this function uses ES6 Proxies, Sets and Symbols. Use Ring.js or similar libaries, if you want an ES5 approach.

You should always prefer other patterns like decorators or annotions if you can, because javascript does not support this for good reasons:

  • must have the same arguments signiture
  • hard to isolate instances
  • overhead

ProxyClass(...mixins)

Uses ProxyScope to reflects all changes to prototype of all mixins.

ProxyClass.hasInstance(...mixins)

Allows the use of instanceof by overwriting all Subclass[Symbols.hasInstance]. Caution: this will make instanceof more expensive.

Examples

const EventEmitter = require('events');
const listen = ["on", "once"];

class ArrayEmitter extends ProxyClass.hasInstance(Array, EventEmitter) {
	constructor(options) {
		let { data } = options;

		super(...data);

		listen.forEach((property) => {
			let type = options[property];

			if(type) {
				for(let event in type) {
					let listeners = type[event];

					if(!Array.isArray(listeners)) {
						listeners = [listeners];
					}

					listeners.forEach((listener) => {
						this[property](event, listener)
					});

				}
			}
		});

		this.emit("push", data);
	}
	push(...args) {
		super.push(...args);
		this.emit("push", args);
	}
}

let input = ["fubar", "haha"];

let ae = new ArrayEmitter({
	data : input,
	on : {
		push(...args) {
			console.log("every push", args);
		}
	},
	once : {
		push(...args) {
			console.log("inital push", args);
		}
	}
});

ae.push("last");

//will be true
na instanceof ArrayEmitter;
na instanceof Array;
na instanceof EventEmitter;

Deep Classes

class A {
  constructor() {
    this.aProp = true;
		this.shared = "sharedA";
  }
  get isA() {
  	return true;
  }
	get sharedA() {
		return this.shared;
	}
	sharedAFn() {
		return this.shared;
	}
}

class B { get isB() { return true; } }

class C extends ProxyClass.hasInstance(A, B) {
  get isC() { return true; }
}

class D {
  get isD() { return true; }
}

class E extends ProxyClass.hasInstance(C, D) {
  constructor() {
      super();

      this.eProp = true;
  }
  get isE() { return true; }
};

//You can also inline your class

var F = ProxyClass.hasInstance(class {
  constructor(someArg) {
      this.someArg = someArg;
      this.fProp = true;
  }
  get isF() {
      return true;
  }
}, E);


var e = new E();

//all of this will return true
e instanceof Object;
e instanceof A;
e instanceof B;
e instanceof C;
e instanceof D;
e instanceof E;

e.isA;
e.isB;
e.isC;
e.isD;
e.isE;
e.aProp;
e.eProp;

var f = new F("fubar");

//same as e plus
f instanceof F;
f.isF;
f.fProp;
f.someArg == "fubar";

Isolation

All class member function will get called with their own isolated context.


expect(e.shared).toEqual("sharedE");
expect(e.sharedA).toEqual("sharedA");
expect(e.sharedAFn()).toEqual("sharedA");

Dependancies

Licence

ISC