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Thoughts on UNIVERSAL::isa More | Login | Reply

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eval? (Score:1)

by Alias (5735)

You surely mean of course (defined $it and blessed $it and $it->isa('Foo'))...
- Re: (Score:2)
  
  by Ovid (2709)
  
  That's a lot longer to type and while it's theoretically clearer, I don't think it wins over an eval. Did I miss something obvious?
  - Re: (Score:1)
    
    by Aristotle (5147)
    
    In general, using eval willy nilly is not good because you might swallow an exception that should have bubbled up. But a properly working isa is not expected to throw exceptions (or so I hope), so this idiom seems just fine.
    - Re:eval? (Score:1)
      
      by chromatic (983) on 2007.12.10 11:56 (#59370) Homepage Journal
      
      You're absolutely right. An overridden isa() that throws an would violate the Liskov substitution principle, so it would not in fact work properly.
      
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