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Comment by techiferous | Hacker News Reader

I'm surprised cadr, caddr, cddr, etc. were not mentioned when comparing car/cdr with first/rest.

See http://www.franz.com/support/documentation/8.2/ansicl/dicten...

Indeed, so was I: the cºr indirections strike me as a very good reason to not switch to `first` and `rest` (or `head` and `tail`) in Lisp: they provide an unambiguous and readable way to quickly traverse multiple levels of datastructures (as long as they're not abused too much) which is not as easy to generally replicate using more meaningful names.

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 would have to stop and really try to grok what list item it was referring to. Not saying that that is a bad thing, just an observation.

Is there a common way of thinking that makes it easier to comprehend, or is it just something that comes with experience?

> 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.)

I worked with Scheme (a type of Lisp) professionally for over a year and even after heavy usage there were still lots of syntax "speed bumps" like this that slowed me down. I really enjoyed a lot of the concepts of Scheme but the syntax was a bummer and I'm so glad I'm not programming with it anymore. :)

Yep Scheme was what I was using with SICP.

I've heard of Common Lisp in passing, does it have a more friendly syntax?

They should have been, since that's one of the best 'current benefits' of the names. (Were I writing the post now, I'd include that argument too.)

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