Recently we decided to read the "Structure and Interpretation of Computer Programs" book through. And not just read it, but also to complete the exercises, given after each chapter. On Friday we had a first meeting, concerning the first chapters we read.
As a working environment the Racket was chosen. It turned out to be a very powerful instrument: not just the language and it's interpretor, but almost a complete IDE with autocomplete, unit tests and even debugging.
That is how errors are shown in Racket. Yes, these arrows are cute.
The meeting was nice and quite productive. We shared some solutions to exercises, and also some were solved just in place. We learned that
(A 2 6)
is a very big number :), where
(define (A x y) (cond ((= y 0) 0) ((= x 0) (* 2 y)) ((= y 1) 2) (else (A (- x 1) (A x (- y 1))))))
P.S. Thanks Anton for the picture :)