madhums madhums

This is a fork of Bootstrap Typeahead that adds minimal but powerful extensions.

For example, process typeahead list asynchronously and return objects

  # This example does an AJAX lookup and is in CoffeeScript
  $('.typeahead').typeahead(
    # source can be a function
    source: (typeahead, query) ->
 # this function receives the typeahead object and the query string

This article has been given a more permanent home on my blog. Also, since it was first written, the development of the Promises/A+ specification has made the original emphasis on Promises/A seem somewhat outdated.

You're Missing the Point of Promises

Promises are a software abstraction that makes working with asynchronous operations much more pleasant. In the most basic definition, your code will move from continuation-passing style:

getTweetsFor("domenic", function (err, results) {
 // the rest of your code goes here.

tl;dr

If you must nest functions in a way that requires access to multiple this', alias outer this to something meaningful - describe the value it's holding. Treat this as the invisible first argument.

In general though, avoiding the situation (nested functions and frivolous use of this) will frequently produce clearer results.

Naming `this` in nested functions

I was accidentally included in a discussion on how to best name this in nested functions in JavaScript. +1's were given to this suggestion of using _this.

Giving style advice on naming nested this without a meaningful context isn't too helpful in my opinion. Examples below have been altered to have at least some context, although a completely contrived and stupid one.

	// See comments below.

	// This code sample and justification brought to you by
	// Isaac Z. Schlueter, aka isaacs

	// standard style
	var a = "ape",
	b = "bat",
	c = "cat",
	d = "dog",

	app.get('/', function(req, res){

	var ua = req.header('user-agent');
	if(/mobile/i.test(ua)) {
	res.render('mobile.html');
	} else {
	res.render('desktop.html');
	}
	});

	var user = {
	validateCredentials: function (username, password) {
	return (
	(!(username += '') \|\| username === '') ? { error: "No Username Given.", field: 'name' }
	: (!(username += '') \|\| password === '') ? { error: "No Password Given.", field: 'pass' }
	: (username.length < 3) ? { error: "Username is less than 3 Characters.", field: 'name' }
	: (password.length < 4) ? { error: "Password is less than 4 Characters.", field: 'pass' }
	: (!/^([a-z0-9_-]+)$/i.test(username)) ? { error: "Username contains invalid characters.", field: 'name' }
	: false
	);

	/*!
	* backbone.collectioncache.js v0.0.2
	* Copyright 2012, Tim Branyen (@tbranyen)
	* backbone.collectioncache.js may be freely distributed under the MIT license.
	*/
	(function(window) {

	"use strict";

	// Dependencies

	var mongoose = require('mongoose');
	var Schema = mongoose.Schema;
	var assert = require('assert')

	console.log('\n===========');
	console.log(' mongoose version: %s', mongoose.version);
	console.log('========\n\n');

	mongoose.connect('localhost', 'testing_1088');
	mongoose.connection.on('error', function () {

	// encode(decode) html text into html entity
	var decodeHtmlEntity = function(str) {
	return str.replace(/&#(\d+);/g, function(match, dec) {
	return String.fromCharCode(dec);
	});
	};

	var encodeHtmlEntity = function(str) {
	var buf = [];
	for (var i=str.length-1;i>=0;i--) {