> Damian:
> > The whole point of having BUILD() is to separate allocation
> > concerns from initialization concerns.

On Thu, 2 Feb 2012, yary wrote:
> And that's not so good, because it forces BUILD to be used for
> initialization, and precludes initializing private attributes anywhere
> else, like a "bless" called from the "new" method.

Err, isn't that the point: BUILD is for initialization, and bless is for

Except that "bless" also does pass-through for to the initializers, which
confuses the mental model. Well, if it's going to do that, perhaps it could
take just one parcel parameter?

(I do find the notion of an inheritable "constructor" a bit odd, upside-down
even. However one of the things I *like* about Perl5 is that a class's
object factory doesn't have to be called "new"; instead it can have a name
that's natural to the domain of the object: File.open, Socket.listen,
Process.run, Timer.start, etc. And object factories can be "instance
methods" too: IO.dup, Socket.accept, String.split, etc.)

The idea of BUILDALL taking care of the hierarchy and each BUILD just
plucking out the named args it needs is quite elegant, but there will
invariably be corner cases where it doesn't fit, particularly if one mixes
in unrelated classes that conflict on their parameter names.

And yet, overriding BUILDALL in an inheritable fashion also seems wrong.

One could revert to the Perl5 and C++ way of doing things: explicitly
calling up the constructor chain. But then how do you make it clear that
BUILDALL is NOT required?

Is there an answer to this conundrum?


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