Practice Makes Perfect

If you haven’t already, you should follow the exact steps detailed in this appendix to build the Roman numeral converter. Don’t stop there, however. Implement the converter a second time, without referring to this book. Think about what the next step should be, build a test, find a simple way to implement it, and refactor your code. Then do it again—maybe not immediately, but perhaps the next day or a week later. Time yourself with each run through the kata, seeking to minimize the keystrokes and effort required to derive a complete solution. If you’ve been away from TDD or C++ for a while, use it as a warm-up exercise.