in reply to Class::Delegation is incompatible with exceptions?

I would say he's to fix the module and send a patch to the author ;-) In this case it seems all you have to do is to change the exception handling code in Class::Delegation so that it only changes some exceptions and rethrows the others without change. (Note I have no idea what is C::D supposed to do.)

Jenda
Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows where you live.
   -- Rick Osborne

Edit by castaway: Closed small tag in signature

  • Comment on Re: Class::Delegation is incompatible with exceptions?

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Re: Re: Class::Delegation is incompatible with exceptions?
by diotalevi (Canon) on Jun 13, 2003 at 15:30 UTC

    I altered my local copy to rethrow exceptions but I don't understand the problem domain well enough to know whether that is a valid thing to do or whether I have to be more careful.

    For anyone that is interested, my alterations:

    # diff -u Delegation.pm~ Delegation.pm
--- Delegation.pm~      Mon Apr 22 23:20:23 2002
+++ Delegation.pm       Fri Jun 13 11:22:45 2003
@@ -53,6 +53,7 @@
                                next DELEGATOR if exists $delegated->{
+$to[0]};
                                foreach my $as (@as) {
                                        push @results, delegate($deleg
+ated,$wantarray,$invocant,$to[0],$as,\@args);
+                                       die $@ if $@;
                                }
                        }
                        elsif (@as==1) {
@@ -60,6 +61,7 @@
                                foreach my $to (@to) {
                                        next if exists $delegated->{$t
+o};
                                        push @results, delegate($deleg
+ated,$wantarray,$invocant,$to,$as[0],\@args);
+                                       die $@ if $@;
                                }
                        }
                        else {
@@ -69,6 +71,7 @@
                                        my $as = shift @as;
                                        next if exists $delegated->{$t
+o};
                                        push @results, delegate($deleg
+ated,$wantarray,$invocant,$to,$as,\@args);
+                                       die $@ if $@;
                                }
                        }
                }

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[d/l]

      I think that the best thing to do would be to change the lines 96-97 from 

                  ? eval { [$target->$as(@$args)] }
            : eval {  $target->$as(@$args)  };

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      to 
                  ? [$target->$as(@$args)]
            : $target->$as(@$args);

      [download]
      I think the eval simply doesn't belong there. We know that the method does exist already thanks to the 
      return unless eval { $target->can($as) };

      [download]
      above and if the method feels like throwing an exception I don't think the Class::Delegate should interfere. I think we should ask TheDamian why is the eval{} there.

      Jenda
      Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows where you live.
         -- Rick Osborne

      Edit by castaway: Closed small tag in signature

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