On Thu, Nov 13, 2008 at 02:55:06PM +0100, Leon Timmermans wrote:
> On Thu, Nov 13, 2008 at 2:24 PM, TSa <[EMAIL PROTECTED]> wrote:
> > Pm wrote:
> > > Presumably the values of a one() junction do not collapse in
> > > this way, otherwise we could easily lose the fact that
> > > a value occurs more than once:
> > >
> > > my $a = (one(1,2,3) % 2 == 1);
> >
> > Do I understand your question right, that you want the return
> > of == to be false because there is a one(1,0,1) junction?
I expect that $a will become one(True, False, True). $a doesn't
collapse to a non-Junction False until it is used in a boolean context.
my $a = one(1,2,3) % 2 == 1;
--> my $a = one(1%2, 2%2, 3%2) == 1;
--> my $a = one(1%2 == 1, 2%2 == 1, 3%2 == 1);
--> my $a = one( True, False, True );
> > As Duncan points out junctions are immutable values and as such
> > the % autothreads but the resulting values are assembled into
> > a new junction according to the general rules, i.e. one(0,1).
> > The number of elements in one(1,2,3) is not preserved.
>
> But of what use would one() if it were to use those semantics? It
> would be essentially the same as any(), and it would definitely not
> DWIM.
I agree that one() with collapsing values isn't dwimmy (or useful),
which is part of the reason for my original message.
Pm
