Re: [External] : Re: How to make M-x TAB not work on (interactive) declaration?

[Michael Heerdegen]

Drew Adams <drew.adams@oracle.com> writes:

> Yes, it's taking a shortcut, supposing that you
> think of a "product" of one arg and a "product"
> of zero args: (* N) -> N, (*) -> 0
>
> But it's fairly common, for programmers at least,
> to consider a "product" function as accepting any
> number of arguments (or accepting a single list
> of any number of elements).

n^0 = 1.  n^0 can be interpreted as an empty product of factors n.

n*0 = 0.  n*0 can be interpreted as an empty sum of summands n.

That's all trivial stuff and used all the time - nobody would ever say
that (* 3 0) ==> 0 is wrong or want to document this case specially.

(+) and (*) are not very different, just a bit less often used in
practice.

Michael.