The repeated expression is only evaluated once, so you are reusing the same anonymous array for each element of the hash. You can map instead of the repetition operator if you want the expression to be evaluated for each repetition.

For example, the problem can be solved by replacing 

my %hash3;
@hash3{keys(%hash3_origin)} =
   ([0, 0]) x keys(%hash3_origin);

[download]
with 
my %hash3;
@hash3{keys(%hash3_origin)} =
   map { [0, 0] } 1..keys(%hash3_origin);

[download]

That said, the following are much simpler: 

my %hash3; $hash3{$_} = [0, 0] for keys(%hash3_origin);

[download]
or 
my @hash3 = map { $_ => [0, 0] } keys(%hash3_origin);

[download]

In reply to Re: Best way to initialize hash x repetition array? by ikegami
in thread Best way to initialize hash x repetition array? by Veltro

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