Size of arrays in a hash

[fagga]

Hello there,

I have a hash of arrays so that I can get my values like this:
my $array_value = $hash{'key'}[0];

My question: How can I find out how many elements the array has? Usually I do this with scalar():
my $size_of_array = scalar(@array);
But this one doesn't work:
my $size_of_array = scalar(%hash{'key'});

Do I have to go through every element of the array in $hash{'key'} and count up while it is defined?

Thanks and greetings,
fagga

 

[fagga]

Well, I just read to few documentation. The solution is:
$hash{'key'} is a reference to an array and I have to dereference it, if I want to use the array. This is done by curly brackets and a @.

$ref_to_array = $hash{'key'};
@array = @{$hash{'key'}};

Anyway, thanks to all the people who would have helped me.

 

[rosenk]

You can still use [tt]scalar[/tt], like:
[tt]my $size_of_array = scalar(@{$hash{'key'}});[/tt]

 

[toolkit]

For example:

%hash = (
  key1 => [ 1,2,3 ],
  key2 => [ 1,2,3,4 ],
  key3 => [ (1..200) ],
);

foreach $key (sort keys %hash) {
  printf "%s points to array of length %d\n", $key, scalar(@{$hash{$key}});
}

Cheers, Neil