Sometimes I see code that is perfectly OK according to the definition of the language but which is flawed because it breaks too many established idioms and conventions of the language. I just gave a 90 minute workshop about Solid C++ Code at the ACCU 2010 conference in Oxford.
When discussing solid code it is important to work on “real” problems, not just toy examples and coding katas because they lack the required complexity to make discussions interesting. So, as a preparation I had developed, from scratch, an NTLM Authentication Library (pal) that can be used by a client to do NTLM authentication when retrieving a protected webpage on an IIS server. Then I picked out a few files, the encoding and decoding of NTLM messages, and tried to write it as solid as possible after useful discussions with ACCU friends and some top coders within my company. Then I “doped” the code, I injected impurities and bad stuff into the code, to produce these handouts. At the ACCU talk/workshop the audience read through the “doped” code and came up with things that could be improved while I did online coding (in Emacs of course) fixing the issues as they popped up. With loads of solid C++ coders in the room, I think we found most of the issues worth caring about, and we ended up with something that can be considered to be solid C++, something that appears to have been developed by somebody who cares about high quality code. Here are the slides that I used to summarize our findings. Feel free to use these slides for whatever you want. Perhaps you would like to run a similar talk in your development team? Contact me if you want the complete source code for the authentication library, or if you want to discuss ideas for running a similar talk yourself. I plan to publish the code on githup soon – so stay tuned.
As a programmer, you’ll find that working hard often does not pay off. You might fool yourself and a few colleagues into believing that you are contributing a lot to a project by spending long hours at the office. But the truth is that by working less, you might achieve more – sometimes much more. If you are trying to be focused and “productive” for more than 30 hours a week, you are probably working too hard. You should consider reducing your workload to become more effective and get more done.
This statement may seem counterintuitive and even controversial, but it is a direct consequence of the fact that programming and software development as a whole involve a continuous learning process. As you work on a project, you will understand more of the problem domain and, hopefully, find more effective ways of reaching the goal. To avoid wasted work, you must allow time to observe the effects of what you are doing, reflect on the things that you see, and change your behavior accordingly.
Professional programming is usually not like running hard for a few kilometers, where the goal can be seen at the end of a paved road. Most software projects are more like a long orienteering marathon. In the dark. With only a sketchy map as guidance. If you just set off in one direction, running as fast as you can, you might impress some, but you are not likely to succeed. You need to keep a sustainable pace, and you need to adjust the course when you learn more about where you are and where you are heading.
In addition, you always need to learn more about software development in general and programming techniques in particular. You probably need to read books, go to conferences, communicate with other professionals, experiment with new implementation techniques, and learn about powerful tools that simplify your job. As a professional programmer, you must keep yourself updated in your field of expertise — just as brain surgeons and pilots are expected to keep themselves up to date in their own fields of expertise. You need to spend evenings, weekends, and holidays educating yourself; therefore, you cannot spend your evenings, weekends, and holidays working overtime on your current project. Do you really expect brain surgeons to perform surgery 60 hours a week, or pilots to fly 60 hours a week? Of course not: preparation and education are an essential part of their profession.
Be focused on the project, contribute as much as you can by finding smart solutions, improve your skills, reflect on what you are doing, and adapt your behavior. Avoid embarrassing yourself, and our profession, by behaving like a hamster in a cage spinning the wheel. As a professional programmer, you should know that trying to be focused and “productive” 60 hours a week is not a sensible thing to do. Act like a professional: prepare, effect, observe, reflect, and change.
[This is a reprint of a chapter that I wrote for the newly released O’Reilly book 97 Things Every Programmer Should Know]
A couple of months ago I bought a Rubik’s cube in a nearby shop and after reading some guides on the net I learned how to solve it. A few hours later I could solve it in about 4 minutes all by myself. After a few days of practice I was down to about 2 minutes, but it was difficult to see how I could improve much further using the beginners method I started out with. My cube and dexterity does not allow me to do more than about 2 moves per second so I realized that I had to reduce the number of moves, rather than speeding up my fingers. After reading several websites about speedsolving techniques I set my self a tough goal – to become a sub-60 cuber. I was determined to study and practice the art of solving the cube until I could solve a Rubik’s cube in less than 60 seconds on average.
I can now often solve it in less than 60 seconds, but I am not stable enough to call myself a sub-60 cuber yet, but I am very close. Give me a few more weeks (or months) and I will get there. While playing with the cube on the bus, at work, at home, in the pub, basically everywhere, all the time, I sometimes meet other geeks that want to learn how to solve the cube fast as well. So I thought I should write up a guide about how to get started.
If you do not know how to solve the cube you need to study one of a billion guides that are available on the net. Here is a beginner solution by Leyan Lo that I recommend. Once you can solve the cube without referring to a guide, you can start to read more advanced stuff. The ultimate guide is written by Jessica Fridrich, but it is not easy to read. I found CubeFreak by Shotaro Makisumi to be the most useful site out there.
After studying these sites, as well as hundreds of other sites and watching plenty of youtube videos, I have ended up with a simplified Fridrich method with a four-look last layer. Here is what I do to solve it in less than 60 seconds:
1. Solve the extended cross ~5 sec (always a white cross)
2. Solve the first two layers (F2L) ~30 sec (keep cross on bottom)
3. Orient the last layer edges ~5 sec (1 out of 3 algorithms)
4. Orient the last layer corners ~5 sec (1 out of 7 algorithms)
5. Permute the last layer corners ~5 sec (1 out of 2 algorithms)
6. Permute the last layer edges ~5 sec (1 out of 4 algorithms)
My current focus is to improve the F2L step as I am still struggling to get under 30 seconds, but I am confident that with some more practice I will manage to get closer to 20 seconds and then I can label myself a sub-60 cuber.