On Mon, Jun 30, 2008 at 01:43:11PM +0200, Moritz Lenz wrote:
> Ovid wrote:
> > --- On Sun, 29/6/08, Patrick R. Michaud <[EMAIL PROTECTED]> wrote:
> >
> >> Do C<grep> and C<reverse> act like the
> >> C<join> method, in that
> >> they work for C<Any> object and not just objects of
> >> type C<List>?
> >>
> >> In other words,, should C< $x.grep(...) > work even
> >> if $x isn't normally a list type?
> >
> > If I understand you correctly, I think you're asking if grep and map can be
> > applied to junctions?
>
> I think Patrick meant something else.
>
> The other day we had the discussion what $x.join($sep) should be,
> specifically if it should work for non-List $x. $Larry said yes, it
> should work, and the way to achieve that is to use Any.join.
> Now Patrick wants to know which of the various list methods need to be
> in Any.
Moritz is correct -- in order to get ('foo').join(':') to work as
people will expect, it was decided to define "universal" methods
in the Any class as part of the prelude [1].
So my question is really whether or not we consider grep and
reverse to be universal methods in this sense also, so that
C< $x.grep(...) > and C< $x.reverse > will work even if $x
isn't a value that normally does list-type operations.
I'm suspecting that the answer is "yes, they are universal",
but wanted to confirm it.
Thanks!
Pm
