From: Robert Klemme <shortcutter@...>
Date: 2007-10-05T17:38:56+09:00
Subject: Re: Reference vs. Reference

2007/10/5, Robert Dober <robert.dober@gmail.com>:
> On 10/5/07, Rick DeNatale <rick.denatale@gmail.com> wrote:
> <snip>
> > Part of the problem with this whole discussion is that it's crossing
> > meta-levels.  Immediates/intrinsics exist in the implementation, below
> > the language level.  To the Java/Smalltalk/Ruby programmer the
> > encoding of object references is invisible.  Object references are
> > object references.
> Not for Java - we can not accept Java in the same league as Smalltalk
> and Ruby can we ? ;).

Um, where's the problem?  Java is a great language and it certainly
has its uses (helps to pay my bills for example).  And don't forget
that several pieces of Ruby were inspired by Java (at least I believe
so).

> While in Smalltalk and Ruby I can and shall handle a Fixnum as an
> imutable object
> in Java I cannot.
> IIRC this fact is somehow hidden in version 1.5+ by some mechanism of
> Autoboxing but I am not sure about that.

Immutability and PODs with autoboxing are different concepts. In all
Java versions (i.e. even prior to 1.5) java.lang.Integer and similar
/are/ immutable.  In fact, with regard to calling semantics this is
the exact equivalent to Ruby.  From a Ruby language user's perspective
immediate values are just an internal optimization that is irrelevant
for parameter passing modes. Rick nicely pointed this out.

Kind regards

robert