I was running my code and came across this error which was really bizarre.

Can't call method "isa" on an undefined value at /usr/local/share/perl
+/5.8.8/Class/Std.pm line 225.

[download]

The problematic code is,

# This is the values that blow it up
#   @hierarchy = qw(EEBL::League::Schedule);
#   @hierarchy = qw(EEBL::Team EEBL EEBL::Config);

    return @{$_hierarchy_of{$class}}
        = sort { $a->isa($b) ? -1
               : $b->isa($a) ? +1
               :                0
               } @hierarchy;

[download]

Does anyone have any ideas on how i can work around this?

Update: My actual solution for this ended up being using another version of Perl on this box (5.10). I don't think the source of my problem was the code but something in the interpreter(5.8.8 on Linux ubuntu 2.6.18.8).

In reply to Class::Std problem by Herkum

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