Dear Monks,

What sort of reasons could there be for the following error message? 

Use of uninitialized value in numeric comparison (<=>) at Permanent.pl
+ line 54, <DATA> line 164.


  my @sorted_files =
      map  { $_->[0] }  # Error message applies here (line 54)
    sort { $a->[1] <=> $b->[1] or $a->[2] <=> $b->[2] }
      map  { [ $_, [stat]->[10], [stat]->[9] ] }  
        @files;

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In reply to Use of uninitialized value in numeric comparison (<=>) error by Win

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