Re: Documentation for car and cdr

[David Kastrup]

Mario Domenech Goulart <address@hidden> writes:

> On Wed, 25 Jan 2006 00:14:32 +0100 David Kastrup <address@hidden> wrote:
>
>> Mario Domenech Goulart <address@hidden> writes:
>>
>>> Wouldn't it be better to write something like "Return the first
>>> element of list" and "Return a list containing all but the first
>>> element of list" for car and cdr, respectively?
>>
>> No.  cons cells don't need to point to an atom in their car, or to a
>> cons cell or nil in their cdr.  This is fundamental Lisp terminology.
>
> Actually I didn't make any assumption about what `element' can be.

But only true lists have elements like those you write about, dotted
lists haven't.

> But admittedly, the text about cdr is faulty, since (listp '(a . b)) is
> t, for example.

I would not call a the first element of a "list" '(a . b).

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum