From: dblack@...
Date: 2007-01-27T21:37:57+09:00
Subject: Re: pass by reference?

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Hi --

On Sat, 27 Jan 2007, Wolfgang N=E1dasi-Donner wrote:

> May be it will be clearer to name an assignment "a =3D someobject" by wha=
t it=20
> really means: "Give a reference to object 'someobject' a name 'a' by=20
> definition". It's close to the ":=3D" used for definition in mathematics.
>
> If one uses this "a" as a "reference to 'someobject'" as an actual parame=
ter=20
> in a method call, it means, that the "reference to 'someobject'" is actua=
lly=20
> used in the method.
>
> Clearly you cannot change "a", because you don't have access to this name=
 "a"=20
> inside the method, but you can change the object "someobject" usually wit=
hout=20
> any problems. If you change "someobject" this will have consequences for =
'a',=20
> because the object ist changed, the reference is still the same.

Right -- I take that as the starting point -- but what I mean is that
the way the assignment/rebinding semantics work doesn't necessarily
pertain to the reference/value question.


David

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