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Postings from October 2022
On Tue, Oct 04, 2022 at 03:40:59PM +0200, Ovid wrote:
> Reviving an old discussion ...
>
> On Mon, Jan 31, 2022 at 9:50 PM Dave Mitchell <davem@iabyn.com> wrote:
>
> > Just to be clear here. I fully expect that function calls will always
> > consist of the caller passing a list to the function, and that the
> > proposed named parameter syntax is just a way of easily processing
> > adjacent pairs of values in that list. So in:
> >
> > sub foo(:$x, :$y) { ... }
> >
> > The caller is expected to pass 4 arguments. How the caller does this is up
> > to the caller. They could do
> >
> > foo('x', 1, 'y', '2');
> >
>
> Since arrays and hashes are flattened into a list, it seems that someone
> might do sub foo(:@bar) {...} and get surprising results. Either it doesn't
> do what they expect, or it's a syntax error. If named arguments can only
> use scalar values, why not drop the sigil?
>
> sub foo (:x, :y) { ... }
I'd expect :@bar to be a syntax error. But note that in a separate
proposal, a \@ary parameter auto-dereferences and aliases a passed array
ref, as in
sub foo(\@numbers) { say "@numbers" }
foo([1,2,3]); # prints "1 2 3"
This can be combined separately with named parameters, giving
sub foo(\:@numbers) { say "@numbers" }
foo("numbers => [1,2,3]); # prints "1 2 3"
--
"Strange women lying in ponds distributing swords is no basis for a system
of government. Supreme executive power derives from a mandate from the
masses, not from some farcical aquatic ceremony."
-- Dennis, "Monty Python and the Holy Grail"
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