RE: 'length' function for lists and cons cells?

[Drew Adams]

> actually I'm looking for a way to distinguish between cons cells and
> regular lists to avoid the errors when mapping an alist that contains
> both with functions that work only on one of them, using 'length' was
> just a hack. 

You distinguish them by the way they are distinguished ;-), i.e., by whether the
cdr of the last cons cell is non-nil.

A true list is either nil or a cons that has a true list as its cdr.  This
implies that it has nil as the cdr of its last cons.

See my previous message.