Jeremy Kahn jeremyckahn

I fight for the users! 💪

jeremyckahn / gist:5649930

Created May 25, 2013 17:25

@varemenos and @jeremyckahn tutoring session notes - 5/25/2013

5/25/2013

jeremyckahn / gist:5607057

Last active December 17, 2015 12:08

Fun code snippet for http://rekapi.com/sandbox.html

	function randomColor() {
	return 'rgb(' +
	parseInt(Math.random() * 256, 10) + ',' +
	parseInt(Math.random() * 256, 10) + ',' +
	parseInt(Math.random() * 256, 10) + ');';
	}

	function randomKeyframe (keyframes) {
	var duration = 0;
	for (var i = 0; i < keyframes; i++) {

jeremyckahn / gist:5561999

Created May 12, 2013 01:07

@getify's saved gist comment #2

	@jeremyckahn

	> This works in ES3 and `Object.create` does not

	Actually, the [non-ES5 polyfilly for `Object.create()`](https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/Object/create#Polyfill) is:

	```js
	Object.create = function(o) {
	function F(){}
	F.prototype = o;

jeremyckahn / gist:5561998

Created May 12, 2013 01:06

@getify's saved gist comment #1

	I don't like this pattern for a variety of reasons, which I went into in detail in a [3-part](http://davidwalsh.name/javascript-objects) [blog](http://davidwalsh.name/javascript-objects-distractions) [post](http://davidwalsh.name/javascript-objects-deconstruction) series, titled "JS Objects".

	The constructor style of coding that wires objects to each other via `[[Prototype]]` by calling constructors "works", but it's more complicated and has many more gotchas than just straight object linking via `Object.create()`. Moreover, the way to think about this mechanism is as "behavior delegation", not "inheritance". If you use constructor-style coding, you opt-in to problems with relative polymorphism, confusion/distraction with the mixin pattern short-circuiting the `[[Prototype]]` chain, etc. Objects linked to other objects really is the simpler model.

	[Update: I'm incorrect asserting an extra object exists in the prototype chain as a result of this pattern. I correct myself in [this comment](https://gist.github

jeremyckahn / inherit-by-proxy.js

Created May 10, 2013 04:25

Proxy-based inheritance pattern in JavaScript.

	function inherit (child, parent) {
	function proxy () {};
	proxy.prototype = parent.prototype;
	child.prototype = new proxy();
	};

	function Parent () {}
	function Child () {}

	inherit(Child, Parent);

jeremyckahn / js-inheritance.js

Last active December 17, 2015 01:39

Simple example of inheritance in JavaScript.

	function Car (licensePlate) {
	this.licensePlate = licensePlate;
	}

	Car.prototype.isLegal = function () {
	return !!this.licensePlate;
	};

	function Mustang (licensePlate) {
	Car.call(this, licensePlate);

jeremyckahn / readonly-string.js

Created May 5, 2013 18:22

Simple example of how to make a read-only string in JavaScript

	function makeReadOnlyString (value) {
	return function () {
	return value;
	};
	}

	var getTestString = makeReadOnlyString('You can\'t modify me!');

	console.log(getTestString());
	getTestString().replace(/^.*$/, 'Yes I can!');

jeremyckahn / animation.html

Created April 27, 2013 21:17

An animation example from a tutoring session.

	<!DOCTYPE>
	<html>
	<head>
	</head>
	<body>
	<canvas style="height: 400px; width: 400px; border: solid 1px #000;"></canvas>
	<script>
	var color = '#f0f';
	var radius = 50;

jeremyckahn / gist:5202638

Created March 20, 2013 06:03

A logarithmic spiral drawn with Python (copy/pasted)

	# Taken from http://nodebox.net/code/index.php/shared_2008-02-26-23-26-39
	# Pasting this here because I want to learn from it.
	# All credit goes to "Mark M." (See source link)
	from nodebox.graphics import BezierPath

	class spiral(BezierPath):
	'''A logarithmic spiral beginning at start_x, start_y and spiraling toward the point end_x, end_y.
	Decay: determines how tightly the spiral turns. Negative values for decay result in the spiral turning
	opposite direction. A value of zero results in a line
	Length: is how many times around the spiril turns.

jeremyckahn / two-rekapi-domactors.html

Created February 14, 2013 04:51

Rekapi example using two DOMActors

	<!DOCTYPE html>
	<html>
	<head>
	<script src="http://rekapi.com/vendor/require.js"></script>
	</head>
	<body>
	<div id="canvas" style="background: #eee; overflow: hidden; height: 500px; width: 600px; position: relative;">
	<img src="http://rekapi.com/demo/img/octocat.png" style="display: none; position: absolute; top: 0; left: 0;">
	<img src="https://www.google.com/images/srpr/logo3w.png" style="display: none; position: absolute; top: 0; left: 0;">
	</div>