From: itsme213 <itsme213@...>
Date: 2005-01-16T00:21:10+09:00
Subject: Re: Duck Typing and automated Conversions


"Robert Klemme" <bob.news@gmx.net> wrote

> Definitely!  But IMHO that weakened the property so much that I ask myself
> whether it's still useful. :-)

I am curious why you think this. After all, anytime I have:
    private_obj = ...
    x = ...
    y = ...
    f x, y

By not passing my 'private_obj' into #f, and based on how f is supposed to
behave, I certainly have some confidence that calling #f(x,y) will not
unexpectedly mess around with private_obj. But, as you pointed out, due to
aliasing via x & y methods called inside #f (as well as other paths through
the object graph) there is no real guarantee of this, other than what I know
about the promised behaior of #f, and my x and y objects.

Despite this, don't you think we rely on such confidence all the time ? :-)