Yesterday in the Barcelona Software Craftsmanship coding dojo we did the Binary Search Tree kata. Raúl Lorca and I paired using TDD in C# to get to a pretty OO solution. We didn't finish the exercise. We got to create the binary search tree but we didn't have time to code the in-order depth-first traversal. Well, it doesn't matter. The important thing is that we practiced TDD, recursion and OO by test-driving a recursive data structure. Today, with a bit more of time, I did the the whole kata i...