in reply to Class::Std problem

That can't be. If @hierarchy only contained one element as you claim it does in the first data set, the compare block would never get called. @hierarchy actually contains more than one element, one of which is undefined.

To see the contents of @hierarchy, you can use 

use Data::Dumper;
print Dumper \@hierarchy;

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Re^2: Class::Std problem
by Herkum (Parson) on Jan 19, 2009 at 05:36 UTC

    I used Data::Dumper to print out @hierarchy. That was how I got the array sample data in the original post. Since I have not debugged Class::Std before I was not sure if this was correct behavior or not.

    Since you are implying it is not, I guess that part needs further looking in to.

    The other thing was I also included code that returned @{$hierarchy_of{$class}} = @hierarchy When it was only a one element array. I still got the same error, which was why I listed two arrays as part of the problem.

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[d/l]

      Sorry, but something you said isn't true. 

      >perl -we"@hierarchy = qw(EEBL::League::Schedule); () = sort { $a->isa
+($b) ? -1 : $b->isa($a) ? +1 : 0 } @hierarchy;"

>perl -we"@hierarchy = qw(EEBL::Team EEBL EEBL::Config); () = sort { $
+a->isa($b) ? -1 : $b->isa($a) ? +1 : 0 } @hierarchy;"

>

      [download]

      According to you, code that isn't even executed is issuing a run-time warning. 

      >perl -we"() = sort { die } 1"

>perl -we"() = sort { die } 1,2"
Died at -e line 1.

>

      [download]

      Find what and you found your problem. The most likely by far is that the content of @hierarchy isn't what you think it is.

      I used Data::Dumper to print out @hierarchy.

      Please provide the output. Remember to use Dumper(\@hierarchy) and not Dumper(@hierarchy). Flattening the array makes the output ambiguous.

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[d/l]
[select]

        Here, is the output that I got from debugging. (Count was used to show the number of elements in the array, so that no undefined elements are sneaking in).

        Dumper $VAR1 = [
          'EEBL::League::Prospect',
          'EEBL',
          'EEBL::Config'
        ];
Count: 3
Dumper $VAR1 = [
          'EEBL::Team',
          'EEBL',
          'EEBL::Config'
        ];
Count: 3
Can't call method "isa" on an undefined value at /usr/local/share/perl
+/5.8.8/Cla                                                           
+                   ss/Std.pm line 228.
Dumper $VAR1 = [
          'EEBL::Team',
          'EEBL',
          'EEBL::Config'
        ];
Count: 3
        (in cleanup) Can't call method "isa" on an undefined value at 
+/usr/local                                                           
+                   /share/perl/5.8.8/Class/Std.pm line 228.
Dumper $VAR1 = [
          'EEBL::League::Schedule'
        ];
Count: 1

        [download]

        I have used Class::Std a lot, and this is the first time I came across this sort of error. I think it just might be a interpreter error because this program was working on another box. I was hoping someone would have any idea of how to work around it without me having to reinstall/update Perl on the machine.

[reply]
[d/l]

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