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10:53:43
makomo
the context is that there's some code which can either returns such a cons or a list of such conses, and it's not enough to just use (consp ...) to detect the former case when lists are made up of conses
10:57:44
makomo
the code is essentially using the "single cons" as a pair of 2 atoms, but technically the car could be a list and you would still be able to distinguish the two cases just fine
11:57:12
pjb
makomo: you can say a cons cell, but if you want a cons cell, nothing prevents it's cdr to be another cons cell.
13:41:21
makomo
pjb: sure, but "dotted list" doesn't describe it exactly, does it? also, wouldn't "dotted list" just refer to the whole notation itself? essentially every list can be dotted if you choose to represent it that way :)
13:43:32
makomo
not quite. i know how to check for it of course and that it's essentially an improper list, etc., but i was wondering if there's some sort of common name for such a structure
13:43:43
mfiano
Well, assuming you're talking about Common Lisp, it is called exactly what pjb said it is called.
13:45:14
mfiano
dotted list n. a list which has a terminating atom that is not nil. (An atom by itself is not a dotted list, however.)
13:45:22
mfiano
dotted pair n. 1. a cons whose cdr is a non-list. 2. any cons, used to emphasize the use of the cons as a symmetric data pair.
13:45:56
makomo
for some reason i forgot to turn to the glossary this time, and instead was just searching elsewhere
13:48:02
makomo
i've seen the concept mentioned a few times around the internet and some people did use the term "dotted pair", but there was no formal reference
13:50:25
makomo
yeah, i'm in there as well, but this was a more general lisp question (and my context was some emacs code i was looking at). however, common lisp has enough weight that i can just use the term for any lisp :)