Brethern --

I want to sort a multidimensional hash by one of it's values and want to be able to build the sort criteria on the fly. I can get this to work fine if it isn't in a subroutine but as soon as I do this in a sub (passing the hash by reference), I start getting wacky results.

I am including the code I have been using to test and wondering what I am doing wrong.

Many thanks in advance,
mdog 

$hash{'Me'}->{"name"} = "Me";
$hash{'Me'}->{"number"} = "7.7";
$hash{'Chuck'}->{"name"} = "Chuck";
$hash{'Chuck'}->{"number"} = "7.7";
$hash{'Zed'}->{"name"} = "Zed";
$hash{'Zed'}->{"number"} = "7.7";
$hash{'Wife'}->{"name"} = "Wife";
$hash{'Wife'}->{"number"} = "7.6";
$hash{'Dad'}->{"name"} = "Dad";
$hash{'Dad'}->{"number"} = "53";
$hash{'Michael'}->{"name"} = "Michael";
$hash{'Michael'}->{"number"} = "24";

test(\%hash);

sub test{
    my($hr) = @_;

    # sort criteria embedded:  expected results
    @sortedKeys = sort { $hr->{$b}->{"number"} <=> $hr->{$a}->{"number
+"} } keys %$hr;
    print "sort criteria embedded\n";
    foreach my $sortedKey(@sortedKeys){
        print $hr->{$sortedKey}->{"number"} . " " . $hr->{$sortedKey}-
+>{'name'} . "\n";
    }
    
    # sort criteria eval-ed: wacky results
    my $sortCriteria = '$hr->{$b}->{"number"} <=> $hr->{$a}->{"number"
+}';
    # WHAT AM I DOING WRONG ON THE NEXT LINE?
    @sortedKeys = sort { eval $sortCriteria } keys %$hr;
    print "\n\nsort criteria eval-ed\n";
    foreach my $sortedKey(@sortedKeys){
        print $hr->{$sortedKey}->{"number"} . " " . $hr->{$sortedKey}-
+>{'name'} . "\n";
    }
}

[download]

The results: 

sort criteria embedded
53 Dad
24 Michael
7.7 Me
7.7 Zed
7.7 Chuck
7.6 Wife

sort criteria eval-ed
53 Dad
7.6 Wife
7.7 Me
7.7 Zed
24 Michael
7.7 Chuck

[download]

In reply to Sorting Hash: Sort Criteria Moved Into Eval by mdog

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