Re: Imitation is the sincerest form of flattery

[amir@iae.nsk.su (Amir Yantimirov)]

Hyman Rosen <hyrosen@mail.com> wrote in message news:<1048530794.5794@master.nyc.kbcfp.com>...
> Dmitry A. Kazakov wrote:
> > IMO. The idea of treating
> >     A[i]=X;
> > as
> >     Assign (Index (A, i), X);
> > is a wrong one.
> 
> Why? In particular, this technique is used very often in C++,
> especially with expression templates. One has Index(A,i) just
> return a proxy class which holds A and i, and implements the
> Assign to take such a class. Inline expansion does the rest,
> usually resulting in code that looks like an open-coded version.

It may be said that any access/reference is too strong contract.
Luckily it is available for free for one-address-space code and
comparatively safe for one-thread one and efficient and simple, yes.
For more complex cases there are property arrays thats don't have
reference semantics and can cover bits access as well.

Amir Yantimirov
http://www174.pair.com/yamir/programming/