morgon:

How about having a simple hash table then? Something like:

my %XMap = (
    'MyException::Class1'=>1,
    'MyException::Class2'=>2,
    ...
);

sub errorcode {
   my $ex = shift;
   my $type = ref $ex;
   return $XMap{$type} if exists $XMap{$type}
   return 3; # default
}
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...roboticus

When your only tool is a hammer, all problems look like your thumb.