From: harryo@... (Harry Ohlsen)
Date: 2002-03-31T08:07:34+09:00
Subject: Re: Creating an instance of a class without calling initialize()

"Joseph Girgis" <jbgirgis@msn.com> wrote in message news:<OE74EzcT1ePyu91wCJW00002df4@hotmail.com>...
> Why don't you want the initialize() method?

Glad someone finally asked :-).

I've been working with Chris Morris's XML serialisation module, which is
really nice. However, what it currently requires is that your initialize
either takes no parameters or has defaults for everything, so that it can
be called with none.  What the deserialisation does is something like ...

    obj = new

    FOR EACH ATTRIBUTE
        obj.send("#{attributeName}=", attributeValue)
    END

where the attribute names and values are retrieved from the XML data.

However, we've been discussing how this is a bit of a restriction,
especially if you're retrofitting the serialisation to a class
hierarchy you've already written.

What you really want is to bypass any initialize that exists, not
force the class designer to make their initialize callable with
no parameters.

I'd been able to make everything work the way I want, but only by
having a separate method in every class that generates a prototype
object (ie, it just calls initialize with some valid set of values)
and wanted to remove that requirement.

The idea about aliasing and then unaliasing initialize should work
for me; I really should have thought of that !!  I'm also intrigued
by the reference to YourClass.allocate() mechanism that's been
mentioned as being in 1.7, so I'll look into that.

Thanks to everyone for the replies.  I just KNEW it could be done in
pure Ruby, but wasn't thinking carefully enough !!