One of the most glorious forms of procrastination for a programmer is developing tools that automate menial and repetitive tasks. I've wasted lots of time on little Python scripts that generate Java classes, remove unused rules from CSS stylesheets, and all kinds of other unnecessary stuff.

My latest invention is a program that does a simple analysis of JavaScript files to determines the order in which they should be concatenated.

Concatenating multiple JS files is a simple optimisation that reduces the number of HTTP requests between a browser and a server. However, they need to be concatenated in the right order so that objects and functions are defined before they are referenced.

The program works by scanning JSLint /*global ...*/ declarations to determine the JavaScript variables referenced by each script. It then looks in all other scripts to figure out which one defines each variable. This results in a dependency graph that maps each file to each of its dependencies.

Once the dependencies are known, the program determines the concatenation order by inserting files into a list, one at a time. Each file is inserted after all its dependencies. If any of the previously inserted files references the newly inserted file, they are removed and reinserted in the same way.

The insertion algorithm seems very inefficient, and possibly isn't even correct! (I don't remember anything about graph theory.) But it seems to work for my Pac-Man project, which is split into 32 interdependent files.

Here's the program, and a Makefile that shows how it's used:

To get really skilful at something, you got to do it a lot. An obvious way to learn games development is by building clones of existing games.

My brother showed me an article that prescribes a list of arcade classics to be developed by the aspiring programmer. Once you remake each of these games, you'll theoretically know all the fundamentals of game development. (This would also be a really good way to learn a new programming language.)

I started on a Tetris clone a long time back then forgot about it. But I recently remembered that I kind of, you know, need to learn how to make games. It's implemented in JavaScript and basically works, although the rotation algorithm is a bit smelly (i.e. wrong). I've pushed it to Github and you can find the source here.

Feel free to use the code in whatever way you like. It's obviously not perfect. I publish it to shame myself into improving it. Hopefully I'll find the time to do so.

Other people's software seems simple until you discover all the little details that accumulate over the life of the program. I won't aim for 100% of the functionality, since it's only a learning exercise. But I will endeavour to add a bit more here and there, possibly in parallel with the next game in the list - Breakout.