in reply to Re: Brain muchly befuddled by nested hashes
in thread Brain muchly befuddled by nested hashes

When you provide a list when referencing a hash element, perl assumes you are using old perl4-style emulated nested hashes and produces a single hash key like this: $ClubTotal{"DayOfMonth$;$date"}.

Based on looking at the OP's output from Data::Dumper (and on trying it myself), it seems that perl is not adding any sort of field delimiter in the hash key: 

perl -le '$n=0; $h{"foo"=>$n++}=$n for (0..3); print "$_ => $h{$_}" fo
+r (sort keys %h)'
foo0 => 1
foo1 => 2
foo2 => 3
foo3 => 4

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That said, I would agree that presence of the "fat comma" (=>) as part of the hash-key expression looks like a misunderstanding (and/or could be misunderstood by less skilled readers), and is rather ugly as well. Something like simple concatenation or string interpolation would be clearer ($hash{'string'.$num} or $hash{"string$num"}).

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Re^3: Brain muchly befuddled by nested hashes
by ysth (Canon) on Nov 24, 2008 at 06:05 UTC
    The delimiter is there, you just don't see it. Hence my comments about Data::Dumper's defaults (added shortly after I first posted, so you may have missed them). 
    $ perl -le '$n=0; $h{"foo"=>$n++}=$n for (0..3); use Data::Dumper; pri
+nt Dumper \%h; $Data::Dumper::Useqq=1; print Dumper \%h'
$VAR1 = {
          'foo1' => 2,
          'foo0' => 1,
          'foo2' => 3,
          'foo3' => 4
        };

$VAR1 = {
          "foo\0341" => 2,
          "foo\0340" => 1,
          "foo\0342" => 3,
          "foo\0343" => 4
        };

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