Did you know that there is a Java build system that does not use angle brackets? More and more projects are using Gradle as an integrated part of their development process. In short, Gradle provides a Groovy DSL for declarative builds based on build conventions. This blog post aims to give you a kickstart if you want to start exploring Gradle yourself by introducing some core concepts and commands. Installation If you have not used Gradle before, you must install…

As we all know, Javascript is a very flexible language. In the article I will show different ways to execute conditional code by using some common idioms from Javascript and general object-oriented techniques. Default values Javascript does not support default values for arguments and it is common to use an if statement or a conditional expression to set default values.

I usually prefer to use an or-expression instead. The short-circuiting or, ||, avoids the repetition of the conditional operator…

Update: This article was written as an April Fool’s joke, taking a stab at the fact that JSON is a closed, dumb, and pretty anemic data format. There are other interesting data formats available, such as extensible data notation (edn). JSON (JavaScript Object Notation) is widely known as JavaScript’s data format, often used as a language-independent data interchange format. However, what I consider to be the three most powerful features of JSON are little-known. The main reason for this is…

Do you want to know how much outgoing traffic there is from your S3 bucket? Maybe your account cost has increased and you need to know what is generating all the traffic. Or maybe you just out of curiosity want to know if your API on S3 is any popular. Fortunately, it is quite easy to get the exact amount of requests and outgoing traffic in four simple steps. 1. Create a new S3 bucket for your access logs. I…

I recently wrote a program, Word Maestro, which requires extensive calculations in Javascript. The calculations, permutations and searching, are very CPU intensive and hangs the GUI when performed in the foreground. Web workers to the rescue! Web workers are supported by most moderns browsers with the exception of IE (Surprise!). IE10 release candidate supports them, but it is not very wide spread yet. More info can be found at Can I Use How do Web Workers Work? A web worker…

If you’re a web developer with prior experience from MVVM/MV* frameworks like Knockout or Batman going into Windows 8 development, one thing you quickly notice is the lack of two-way binding when using the WinJS template control. In this blog post we´re going to show you a starting point to roll your own two-way binding without going to another lib, when binding a simple view model to a view with a WinJS template. Intro When working with the ListView control…

This week I released the neo4j-cypher ruby gem version 1.0.0. Cypher queries can now be written in Ruby instead of as a long string. The DSL uses common Ruby conventions and a neo4j.rb influenced API. The neo4j-cypher gem contains adaptors for both the neo4j.rb and neography gems. The DSL supports the cypher language implemented in the 1.8 release of neo4j which just have been released. Introduction to Neo4j and Graph Databases Using a graph database means that you store your…

Most web developers have realized that Javascript is a first-class citizen in web development, but the same is not true of CSS. CSS is still "the wild west" and I believe that this is because CSS falls between the chairs of developers and designers. CSS is also a first-class citizen and it needs as much love as Javascript to avoid becoming a maintenance nightmare. Here are some ideas that I believe are good practices to follow. Use a pre-processing language…

I recently rolled my own Decimal to Roman Numeral converter in Clojure. I was inspired by some tweets about a roman numeral code kata. The Decimal to Roman Numeral converter takes a decimal number (like 2012) and returns a string of roman numerals (like “MMXII”). The code that I came up with is around ten lines that look like this: (def mapping (sorted-map-by > 1000 "M" 900 "CM" 500 "D" 400 "CD" 100 "C" 90 "XC" 50 "L" 40 "XL"…

One thing I miss in the tools and templates around HTML5/Javascript development for Windows 8 is a test strategy, or at least some encouragement in the templates to send you in that direction. There is no test runner for metro apps using Javascript in the tools today.  Internally Microsoft would have some test support, but not yet public tooling. A test runner in VS would be nice, and a strategy to run tests in CI/deploy/build process, like the Team City…

During a recent re-factoring of some JavaScript I accidentally removed the last line of a function that told the UI to re-render according to the new data. After that I figured, why not move this outside of the function and get a little AOP look and feel. The code below gives a simplified version of the problem. Foo.Bar=function(){ var someValue; var self={ foo:function(addThis){ someValue+=addThis; rerender(); //This line have to be here… } }; return self; }(); So with that in mind I created the three obvious methods, before, after and…

Imagine that you one day were asked to implement the following requirement: “As an Administrator, I want to know what has changed in the database since a given timestamp, and also who made the changes, so that I can feel secure that nobody will screw up the database.” In most projects, this would give you a major headache. There is no notion of time in a database. There might be a transaction log you could look in, or perhaps some…

On the 14th of May 2008 the first commit was made. Now, four years, 2045 RSpecs and 1480 commits by 31 contributors later Neo4j.rb has reached version 2.0. Here are some of the news: The neo4j gem has been split up into three gems, neo4j-core, neo4j-wrapper and neo4j Lots of refactoring (which probably also means better performance) More consistent API Cypher DSL with Rule integration. In this blog I will give you an overview of Neo4j.rb. Neo4j.rb – a New…

This example assumes that you have a Github account. If you don't have one, you can get one at (suprise!) Github. It also assumes that you have installed Node and npm. It will also simplify your life to have the github gem installed Create the basic structure

OK, now I have an initialized repository and I need something to put in it. I like Readme Driven Development and, in that spirit, let's create a Readme.

`sleep-sort` works by…

Recently I got to use the Google Maps Javascript API for the first time, which was a quite pleasant experience. The API is thoroughly documented and most of the parts I used just worked on the first try. This post tries to show how easy it is to use the Google Maps API for showing a dynamic map on a web page with some additional stuff added to it. The Use Case The first step I did was to use…

During the Software Passion Summit in Gothenburg, I had the privilege to talk to Douglas Crockford, the grandfather of Javascript and the creator of JSON and JSLint While I think that JSLint is an awesome tool, I also think that it is too opinionated and therefore I use JSHint, an alternative that allows me to tweak more of the parameters to fit my style of coding. Douglas think that this is sacrilege, but I disagree. There are two major things…

This post is the final part of a series of articles about LISP, a function called SUBST, Clojure, and other interesting stuff. You probably want to read the previous posts before continuing with this. Part 1: Introducing LISP Part 2: Walking through SUBST Part 3: Clojure version of SUBST In part 1 of this series, we learned about the nine special forms of LISP, the building blocks that make up the language. In part 2, we went through how the…

This post is part of a series of articles about LISP, a function called SUBST, Clojure, and other interesting stuff. You may want to read the previous posts before continuing with this post. Part 1: Introducing LISP Part 2: Walking through SUBST In part 1 of this series, we learned about the nine special forms of LISP, the building blocks that make up the language. In part 2, we went through how the SUBST function works on a small tree….

This post is part of a series of articles about LISP, a function called SUBST, Clojure, and other interesting stuff. You may want to read the previous post before continuing with this post. Part 1: Introducing LISP In part 1 of this series, we learned about the nine special forms of LISP, the building blocks that make up the language. In this part we will go through how the SUBST function works on a small tree. When John McCarthy in…

When John McCarthy in 1960 wrote his famous paper on the programming language LISP, he used a particular function to illustrate what you could do with the language. The language consisted of only nine “special forms”, primitive building blocks by which any computable function could be created. The function was called SUBST, and it included all nine of the special forms. It was a remarkable function. It could rip through any tree and replace all leaves that had one value…

Note: This article is unfortunately outdated. Please se this tutorial on how to create your own acvanced custom field types. To get the most out of this article a basic knowledge of PHP, WordPress, custom post types and Advanced Custom Fields is required. If you’ve ever needed custom data input for your WordPress posts or pages (or any other kind of custom post type) then Advanced Custom Fields (ACF) is the shit! It’s flexible, extensible and frequently improved by Elliot…

New to Capistrano? Read my previous and more introductory blog post on Capistrano – Remote builds with Capistrano. Are you using Capistrano and are confused why the user environment, the PATH for example, is different from when you log on to your server via SSH? Perhaps you have failed to use RVM or other user specific applications when running your Capistrano scripts? This post will explain why this is, and what can be done to solve the problem. By default…