> Maybe it's just my mental model, or being new to the language. But while going through SICP - 'cdadadr', 'cddaadr', etc. never really "clicked" in my mind. Re

> Maybe it's just my mental model, or being new to the language. But while going through SICP - 'cdadadr', 'cddaadr', etc. never really "clicked" in my mind. Really anything past 3 levels (cadar, cddar, etc.) always slowed down reading code, like hitting a speed bump I've used Lisp for a while, and where I tend to wind up on these composite forms is that I use a few of the simpler composites, but tend to switch to either destructuring-bind or some other data type if it gets too complex. (Practically speaking, that means anything much beyond 'car', 'cdr', and 'cadr' gets refactored.)