Can't you simply drop your reference to unwanted objects?

   @objects = grep { $_->is_relevant } @objects;
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that'll throw away the ref to the object and (if there are no other references), the object will be destroyed. If you have other references, then the normal answer to that (mentioned elsewhere) is to make them weak references (which means they won't keep the object alive, but become undef when the object goes away).

I think that latter case (keeping other references around, so having to have them weak) is pretty unusual, though. Would you mind giving us a little more detail about your problem?