You created a single Hash then assigned it to two variables.
Also `clone` always does a shallow clone.
So there will be two Hashes, but the values will still share the same
scalar container.
If you add a new key it won't be in the other Hash.
my $a = { a => 1 };
my $b = $a.clone;
$b<b> = 2;
say $a; # {a => 1}
say $b; # {a => 1, b => 2}
$b<a> = 3;
say $a; # {a => 3}
You could work around that by deleting the key first.
$b<a>:delete;
$b<a> = 5;
Or by creating the second Hash some other way
my $b = %( $a.pairs );
my $b = %( $a.kv );
my %b = $a;
Which shows that if you are dealing with a Hash it is probably better
to use a % variable.
If you want to define the type of Hash-like container you can:
my %b is Hash = $a;
my %b is BagHash = $a;
my %b is Bag = $a; # immutable
On Sun, Mar 24, 2019 at 6:11 AM Marcel Timmerman <mt1...@gmail.com> wrote:
>
> Hi,
>
> I was wandering if the following is an assignment or a binding (or binding of
> the entries);
>
> my Hash $sleep-wait = { :s1(4.3), :s2(2.1), :s3(5.3), :s4(10.4), :s5(8.7),};
>
> my Hash $sleep-left = $sleep-wait;
>
>
>
> I noticed that in the following piece of code the $sleep-wait hash entries
> were set to 0
> I had to explicitly do a copy to let it function correctly; 'my Hash
> $sleep-left = %(|$sleep-wait);'
> Also cloning didn't work.
>
> use v6;
>
> my Hash $sleep-wait = {
>
> :s1(4.3), :s2(2.1), :s3(5.3), :s4(10.4), :s5(8.7),
>
> };
>
> my Hash $sleep-left = $sleep-wait;
>
> loop {
>
> # get shortest sleep
>
> my $t = 1_000_000.0;
>
> my $s;
>
> for $sleep-left.keys -> $k {
>
> if $sleep-left{$k} < $t {
>
> $t = $sleep-left{$k};
>
> $s = $k;
>
> }
>
> }
>
> # set back to original time
>
> $sleep-left{$s} = $sleep-wait{$s};
>
> note "Reset entry $s to $sleep-left{$s} (from $sleep-wait{$s})";
>
> # adjust remaining entries
>
> for $sleep-left.keys -> $k {
>
> next if $s eq $k;
>
> $sleep-left{$k} -= $t;
>
> $sleep-left{$k} = $sleep-wait{$k} if $sleep-left{$k} <= 0;
>
> }
>
> note "sleep for $t sec, entry $s";
>
> sleep $t;
>
> }
>
>
> perl version;
>
> This is Rakudo version 2018.12-363-ga1c2e20d7 built on MoarVM version
> 2018.12-117-gdcafbc4c7
> implementing Perl 6.d.
>
>
> Regards,
> Marcel
