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;

[download]

In reply to Re: Class::Std problem by ikegami
in thread Class::Std problem by Herkum

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