I've already discussed this a bit on the chatterbox, but I'm still not satisfied that it isn't possible.

Say I've created an object with some class' new() method, and have references to it in various places. If I then want to replace the object - in all of these places - with another one, the intuitive thing doesn't work: 

$a_ref_to_the_object = Class->new;

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as it only changes that one reference.

The following hack does work, but only if the object is stored internally as a hash: 

%$a_ref_to_the_object = %{Class->new};

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However, this assumption is A Bad Thing, as the code will fall over if the internal representation changes. It also will not work if the object is tied.

This would work in a more general way: 

sub retarget_ref {
    my ($old, $new) = @_;
    ref $old and ref $new or return;
    local $SIG{__DIE__}; # disable any user error handlers
    
    eval { $$old = $$new }; $@ or return;
    eval { @$old = @$new }; $@ or return;
    eval { %$old = %$new };
}

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but it would still fail if the object was tied, and it pains me to rely on eval()'s exception trapping.

Is there a simpler, more general, or otherwise nicer way?

In reply to Changing the target of refs of unknown type by Irrelevant

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