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Answer: How do I make deterministic constructors?

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Q&A > object-oriented programming > How do I make deterministic constructors? contributed by herveus



sub new { if (@_ == 2) { new_1(@_); } elsif (@_ == 1) { new_2(@_); } else { warn "bad parameter..."; } }
where subs new_1 and new_2 are your alternatives. You can do more detailed checking of the characteristics of the contents of @_ as needed. Of course, there is Class:Multimethods as mentioned earlier to automate this.


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Re: Answer: How do I make deterministic constructors?
by Hofmator (Curate) on Aug 29, 2001 at 18:23 UTC

    I'd suggest using the goto &subroutine syntax for this case:

    sub new { if (@_ == 2) { goto &new_1; } elsif (@_ == 1) { goto &new_2; } else { warn "bad parameter..."; } }
    The benefit of this is that in every respect (e.g. for caller or croak) it looks like new_1 (or new_2) have been called directly - and not through new.

    -- Hofmator

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