Not Bad

Very few things strike more fear into me than the statement that something's "Not Bad".

"You should give this a listen, it's not bad."
"You should go see this film, it's not bad."
"You should waste 2 hours of your time on this, it's not bad."

I don't want things that are 'not bad', not bad isn't a compliment, it's a statement of dull mediocrity. I want great things, exciting things, things that take me to strange far-away places and show me sights that I haven't seen before. If the most that something is able to inspire you to in recommendation is "not bad" then I really have better things to do with my time. I demand that something be at least 'good' before I spend my time on it. On the other hand, if you find something of indescribable awfulness, then I may well be tempted. But it'd better be pretty bloody awful.

Testing Testing

Another good thing from Extreme Programming - testing suites. The idea is that you create a test suite for each program _before_ you create it. Your program is working only when it passes all of the tests. You add tests as you spot possible ones during the coding and re-run the tests whenever you change the code.

I was handed an old COBOL program, written in he COBOL-74 standard (as in 1973) and told to bring it up to date in COBOL-85 (and yes, there is a COBOL 2000, but we're not getting that for another year or two). I did a bit of rewriting before I realised that while I was pretty sure that my changes so far hadn't changed functionality, I couldn't be 100% sure. So I wrote a test suite to call the program with 15 different combinations of data (it's a fairly simple program) and made sure that the tests all passed ok. Then, whenever I refactored some code after that, I'd recompile and re-test. If the test suite passed, that meant that my new code hadn't done anything seriously different. I added a few tests as I went along, when my changes added new branches into the code.

Because I knew that my changes definitely worked, I felt far less worried about the effects my code changes were having. I could happily move whole chunks around, provided I re-ran the tests straight afterwards to spot any errors that had crept in. A 150-line program swiftly became a 30 line program - and I know that it's right, because it does exactly the same as the old program did with the same data.

I'll definitely be doing more of that in the future.

My eyes!!!!

A page of fantastic optical illusions