in reply to Re: Re (tilly) 2: Paradigm Shift - Dual Use Constructors
in thread Paradigm Shift - Don't use strict

When I call GA::Entity->new() it returns a randomly generated solution. When I call $ga_entity->new() it produces a randomly mutated version of $ga_entity, and when I call $ga_entity->new($other_ga_entity) it returns a cross of the two. I thought long and hard if I wanted this type of behaviour and experimented with a number of alternatives before deciding I was happy with this approach. But of course merlyn would mark me down bigtime without considering why I had done it, and what my reasons were.

I fail to see how someone would mark you down on this, because you wouldn't have the traditional my $class = ref($proto) || $proto, you would have something much more complex wrapped around: 

if (ref($proto)) {
  if (ref($_[0])) { 
    cross polinate
  }
  else { 
    mutate 
  } 
} 
else {
  construct new
}

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Which would look far more reasonable in a code review, and would almost inevitably have to be documented. So I don't buy your argument.

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Re: Re: Re: Re (tilly) 2: Paradigm Shift - Dual Use Constructors
by demerphq (Chancellor) on Feb 20, 2002 at 09:59 UTC
    Hmm. Interesting angle. But ircc (its on my home computer) the code went more like 
    sub new {
   my $proto=shift;
   my $class=$proto || ref $proto; 
   my $self=bless {},$class;
   if ($class eq $proto) { #class call
       $self->init_rand();
   } elsif (@_) {
       $self->init_cross($proto,shift);
   } else {
       $self->init_mutate($proto);
   }
   return $self
}

    [download]
    So the dreaded line was/is present. But you are correct I did/would comment this.

    Yves / DeMerphq
    --
    When to use Prototypes?

[reply]
[d/l]

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