PPL: Day 18 - Emergence
I’m trying really hard not to treat this chapter as a throwaway. Clearly, the author included it for a reason, but it’s so small!
Today’s reading: Pg 171 - pg 176
This chapter was actually pretty darn good. It boils down a lot of critical concepts from the preceding text. Where the earlier chapters provided an excellent foundation of tactical (and increasingly strategic) methodologies, this chapter moved over the delivering some excellent big picture thinking. It summarizes the previous chapters beautifully using a few key rules from Kent Beck’s Extreme Programming Explained (which I’m going to reproduce from Martin Fowler’s blog):
In XPE Kent gives four criteria for a simple system. In order (most important first):
- Runs all the Tests
- Reveals all the intention
- No duplication
- Fewest number of classes or methods
There’s a LOT of meat there. I can see this heuristic becoming extremely valuable.
My biggest fault at this point is probably duplication. I really need to work on strategies for reducing duplication in my code. This challenges me to push harder on refactoring once my tests pass and the functionality works.