On Fri, Jul 31, 2015 at 4:16 PM, Moritz Lenz <mor...@faui2k3.org> wrote:
>
>
> On 07/31/2015 03:02 PM, Gabor Szabo wrote:
>
>> The following code (with comments) is confusing me.
>> Can someone give some explanation please?
>> Specifically the difference between
>>
>> my @x = <a b>;
>>
>
> It's the assignment to the Array variable that makes the Array here; < >
> by itself just creates a Parcel:
>
> $ ./perl6-m -e 'say <a b>.^name'
> Parcel
> $ ./perl6-m -e 'say (my @ = <a b> ).^name'
> Array
>
> # we can assign that array to a scalar variable and it is still and array
>> my $y = @x;
>>
>
> that's because assignment to $ isn't coercive in the same way as
> assignment to @ or %.
>
> It just wraps things into a Scalar, which is normally invisible.
>
> But, you can observe the difference still>
>
> my @a = <a b>;
> my $s = @a'
>
> for @a { } # two iterations
> for $s { } # one iteration
>
>
Thanks though this just shows I still don't get the whole sigil and Array
thing in Perl 6.
I thought you can put an array in a $ -ish variable and that will still be
a real array, but
now I see it is not an array.
use v6;
my $z = ['a', 'b', 'c'];
say $z.^name; # Array
for $z {
say $^a; # a b c (single iteration)
}
say $z.elems; # 3
# assigning it to a @-thing does not convert it to a real array either:
my @a = $z;
say @a.^name; # Array
for @a {
say $^a; # a b c (single iteration)
}
say @a.elems; # 1
# and even
say @a[0].^name; # Array
for @a[0] {
say $^a; # a b c (single iteration)
}
say @a[0].elems; # 3
# explicitly converting a fake(?) Array to an Array works...
my @x = $z.Array;
say @x.^name; # Array
for @x {
say $^a; # (3 itterations)
}
say @x.elems; # 3
Probably it has another name and you don't call it "fake" array, do you?
Gabor
