I may be wrong there, but the debugger seems to agree.

I don't see how the debugger can agree with that. Let's set up a multidimensional array and see what happens! 

use Data::Dumper;

my @multi;
foreach my $i ( 10 .. 12 ) {
    foreach my $j ( 10 .. 12 ) {
        $multi[$i-10][$j-10] = "$i,$j";
    }
}
my $what_is_this = $multi[1];
print Dumper $what_is_this;
__END__
$VAR1 = [
          '11,10',
          '11,11',
          '11,12'
        ];

[download]

The code in question actually gets a reference to an array, which is what's output by Data::Dumper.

To get the number you're talking about, the syntax would be: 

my $n = scalar @{ $multi[1] };

[download]

The use of scalar is not needed functionally, but it makes it easier to see what's meant.

In reply to Re^6: How to speed up a nested loop? by kyle
in thread How to speed up a nested loop? by Xenofur

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