Re: Documentation for car and cdr

[Miles Bader]

Alan Mackenzie <address@hidden> writes:
> Others have asserted that "cdr returns the cdr" is a coherent
> description of cdr.  They are thus implying that "cdr" is semantically
> different from "cdr", otherwise that description would be circular and
> vacuous.

Er, well they _are_ different in that sentence -- the first "cdr" is a
function, the second "cdr" is the name of part of a data-structure.

I guess this thread has become a bit overblown (this is a minor issue!),
but I agree that in some cases it might nice to describe the "list
meaning" of such functions as an addendum, to help beginners.

E.g.

   Return the cdr of the cons-cell CONS.  If CONS is nil, return nil.
   Signal an error if CONS is not nil and not a cons cell.
   See also `cdr-safe'.

   When CONS is interpreted as a list, cdr returns the list tail
   (the list with the first member removed).

-miles
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