Dennis Rongo menacestudio

## gist:36c8d1d246a94098c16b

      
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                menacestudio
                / gist:36c8d1d246a94098c16b
            
            
              Last active
              August 29, 2015 14:19
                — forked from bvaughn/gist:012fb525e6c819fdc9bf
            
          
    This afternoon I encountered a race condition in an Angular app I'm working on. Essentially my controller was pushing some values to an Array on its scope and something (I wasn't sure what) was asynchronously overriding the Array's contents. The Array was being used by a custom directive- written by someone else- as well as an ngModel and it wasn't clear who was making the change.
I ended up trying something I had not done before and it worked well enough that I thought I'd post it here in case it helped anyone else.
First I enabled The "Async" option in Chrome's "Sources > Call Stack" panel.
Next I set a breakpoint in my controller where I was modifying the Array. When I hit that breakpoint, I ran the following code in my console:
Object.observe(this.theArray, function(changes) {

  
## 0_reuse_code.js
// Use Gists to store code you would like to remember later on
console.log(window); // log the "window" object to the console

## HttpRequestMessageHelper.cs
// Original idea: http://stackoverflow.com/questions/9565889/get-the-ip-address-of-the-remote-host

using System.Net.Http;
using System.ServiceModel.Channels;
using System.Web;

namespace CrowSoftware.Api
{
    public static class HttpRequestMessageHelper
    {

## paginated_collection.js
// includes bindings for fetching/fetched

var PaginatedCollection = Backbone.Collection.extend({
  initialize: function() {
    _.bindAll(this, 'parse', 'url', 'pageInfo', 'nextPage', 'previousPage', 'filtrate', 'sort_by');
    typeof(options) != 'undefined' || (options = {});
    typeof(this.limit) != 'undefined' || (this.limit = 20);
    typeof(this.offset) != 'undefined' || (this.offset = 0);
    typeof(this.filter_options) != 'undefined' || (this.filter_options = {});
    typeof(this.sort_field) != 'undefined' || (this.sort_field = '');

## gist:4515310
/*
 * Extends Handlebars with a basic get method for loading external
 * Handlebars templates. Simply pass an options object which contains
 * the following properties:
 * - path    (required) : Path to the external template file to be loaded
 * - success (required) : Callback invoked with the compiled loaded template.
 * - cache   (optional) : true if the template is to be cached, otherwise false.
 *
 * In addition to the above arguments, any jQuery/Zepto.ajax options argument
 * can be specified as well.

## gist:4509238
define(['handlebars','text'], function (Handlebars, text) {

  var _buildMap = {};
  var _buildTemplate = Handlebars.compile(
                         'define("{{pluginName}}!{{moduleName}}", ["handlebars"], function(Handlebars){'+
                         '  return {{fn}}'+
                         '});\n'
                       );
  return {
    load: function (name, req, onLoad, config) {

## example.html
Choose a ticket class: <select id="tickets"></select>

<p id="ticketOutput"></p>

<script id="ticketTemplate" type="text/x-jquery-tmpl">
    {{if chosenTicket}}
        You have chosen <b>${ chosenTicket().name }</b>
        ($${ chosenTicket().price })
        <button data-bind="click: resetTicket">Clear</button>
    {{/if}}

## jquery.loadasync.js
// Load scripts asynchronously
jQuery.loadAsync = function(url, callback) {
	// Don't use $.getScript since it disables caching
	jQuery.ajax({
		'url': url,
		'dataType': 'script',
		'cache': true,
		'success': callback || jQuery.noop
	});
};

## jspat6_4.html
<html>
<head>
<title>Chapter 6 Section 4, Pro JavaScript Design Patterns</title>
</head>
<body>
<script>

// this is straight from the code exampes at http://jsdesignpatterns.com/
// sadly, it fails with a syntax error.  quoth JSLint:
//

## gist:2026647
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
<script>window.jQuery || document.write('<script src="js/libs/jquery-1.7.1.min.js"><\/script>')</script>
	// Use Gists to store code you would like to remember later on
	console.log(window); // log the "window" object to the console
	// Original idea: http://stackoverflow.com/questions/9565889/get-the-ip-address-of-the-remote-host

	using System.Net.Http;
	using System.ServiceModel.Channels;
	using System.Web;

	namespace CrowSoftware.Api
	{
	public static class HttpRequestMessageHelper
	{
	// includes bindings for fetching/fetched

	var PaginatedCollection = Backbone.Collection.extend({
	initialize: function() {
	_.bindAll(this, 'parse', 'url', 'pageInfo', 'nextPage', 'previousPage', 'filtrate', 'sort_by');
	typeof(options) != 'undefined' \|\| (options = {});
	typeof(this.limit) != 'undefined' \|\| (this.limit = 20);
	typeof(this.offset) != 'undefined' \|\| (this.offset = 0);
	typeof(this.filter_options) != 'undefined' \|\| (this.filter_options = {});
	typeof(this.sort_field) != 'undefined' \|\| (this.sort_field = '');
	/*
	* Extends Handlebars with a basic get method for loading external
	* Handlebars templates. Simply pass an options object which contains
	* the following properties:
	* - path (required) : Path to the external template file to be loaded
	* - success (required) : Callback invoked with the compiled loaded template.
	* - cache (optional) : true if the template is to be cached, otherwise false.
	*
	* In addition to the above arguments, any jQuery/Zepto.ajax options argument
	* can be specified as well.
	define(['handlebars','text'], function (Handlebars, text) {

	var _buildMap = {};
	var _buildTemplate = Handlebars.compile(
	'define("{{pluginName}}!{{moduleName}}", ["handlebars"], function(Handlebars){'+
	' return {{fn}}'+
	'});\n'
	);
	return {
	load: function (name, req, onLoad, config) {
	Choose a ticket class: <select id="tickets"></select>

	<p id="ticketOutput"></p>

	<script id="ticketTemplate" type="text/x-jquery-tmpl">
	{{if chosenTicket}}
	You have chosen <b>${ chosenTicket().name }</b>
	($${ chosenTicket().price })
	<button data-bind="click: resetTicket">Clear</button>
	{{/if}}
	// Load scripts asynchronously
	jQuery.loadAsync = function(url, callback) {
	// Don't use $.getScript since it disables caching
	jQuery.ajax({
	'url': url,
	'dataType': 'script',
	'cache': true,
	'success': callback \|\| jQuery.noop
	});
	};
	<html>
	<head>
	<title>Chapter 6 Section 4, Pro JavaScript Design Patterns</title>
	</head>
	<body>
	<script>

	// this is straight from the code exampes at http://jsdesignpatterns.com/
	// sadly, it fails with a syntax error. quoth JSLint:
	//
	<script src="//ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
	<script>window.jQuery \|\| document.write('<script src="js/libs/jquery-1.7.1.min.js"><\/script>')</script>