On Thu, Sep 01, 2005 at 08:09:41PM -0700, Yitzchak Scott-Thoennes wrote:
> On Thu, Sep 01, 2005 at 09:20:07PM -0400, Rick Delaney wrote:
> > On Thu, Sep 01, 2005 at 05:41:36PM -0700, Yitzchak Scott-Thoennes wrote:
> > > On Wed, Aug 31, 2005 at 06:07:11AM -0700, japhy @ perlmonk. org wrote:
> > > > sub foo { ...; return @data }
> > > >
> > > > my $x = (foo())[0][1];
> > > >
> > > > which would have the same effect as
> > > >
> > > > my @return = foo();
> > > > my $x = $return[0][1];
> > > >
> > > > However, it's a syntax error.
> > [...]
> > > I don't see any reason not to just make it legal syntax instead:
> >
> >
> > What is
> >
> > my $x = (foo())[0..5][1];
> >
> > supposed to mean? I know it will return (foo())[5][1] but is it a good
> > idea to support this syntax when it looks it might mean some kind of
> > multidimensional slice? To me it looks like
> >
> > map { (foo())[$_][1] } 0 .. 5;
>
> I don't see any difference between your case above and
>
> my $x = (foo())[0..5];
>
> which also doesn't warn.
>
> > And if that syntax is ok, why not
> >
> > my $x = @array[0..5][1];
>
> Because I couldn't conceive of a use for it? There is separate syntax
> for getting a single element or multiple elements of an array or hash,
> but only one syntax for both cases for a list.
>
> > ? I think a warning is in order at least. We already have
> > "Multidimensional syntax %s not supported" for
> >
> > $array[0,1][1];
>
> A warning would be good, but I don't think it's necessary before applying
> my patch, and presumably it would also apply to
>
> @array[0..5]->[1];
I mean (foo())[0..5]->[1];
> whereas
>
> @array[ (0..5)[-1] ]->[1];
I mean ( (foo())[0..5] )[-1]->[1]
> shouldn't warn with or without the ->.
To summarize, the issue of slices of whatever kind being used in a
scalar context is a separate issue from whether the -> should be
required before dereferences following a list slice.
