Re:What does “my other car is a cdr” mean?
by gm-conspiracy on Thursday May 25, 2017 @09:24AM
(#14417099)
CDR is the "input" to CADR and the result is CAR?
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Re:What does “my other car is a cdr” mean?
by kaushalmodi on Thursday May 25, 2017 @09:49AM
(#14417252)
If you have a list `(Odyssey Model-S)`, `car` will be `Odyssey`, `cdr` will be a list `(Model-S)`. You yet need to do a `car` on that.. So `(car (cdr ..))` will give you `Model-S`. `(cadr ..)` is short for `(car (cdr ..))`.
Re:What does “my other car is a cdr” mean?
by ball_of_lint on Thursday May 25, 2017 @09:46AM
(#14417226)
Not exactly, cadr is what you would get if you called CDR on a list, then car on the result of that. Lisp has several of these types of chains.
Since cdr always returns a list, to get a single item you would need to call car on it, therefore cadr.
Re:What does “my other car is a cdr” mean?
by ambulancechaser on Thursday May 25, 2017 @11:58AM
(#14418095)
someone mentioned it earlier but it's not true that cdr always returns a list, for instance, `(cdr `(1 . 2))`