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in reply to How do I make deterministic constructors?

Howdy!

Consider: 

sub new
{
    if (@_ == 2) { new_1(@_); }
    elsif (@_ == 1) { new_2(@_); }
    else { warn "bad parameter..."; }
}

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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.

yours,
Michael

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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..."; }
}

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    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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