RE: [sv-bc] [Fwd: Issues with IEEE 1364-2005]

>Programmers who invoke operations with side-effects in such a context
deserve
>any surprises they may get :-)

On the contrary, users deserve to get what they've always got.  Legacy
code is indeed a legacy, and we can't afford to squander it.

Expert hardware designers are not necessarily expert C programmers.

I'm a programmer, not a hardware designer.  Yet even I prefer a
parallel, functional style of programming that is easy to reason about,
and I find C's sequentializing, left-to-right bias weird and
unnecessary.  What's the big advantage of being able to write

    if (guard && side_effector)

instead of the more transparent

    if (guard)
      if (side_effector)

?  To me, it would make more sense to say that a side-effecting
expression shall not be the operand of an && or ||.

-- Brad

-----Original Message-----
From: owner-sv-bc@eda-stds.org [mailto:owner-sv-bc@eda-stds.org] On
Behalf Of Jonathan Bromley
Sent: Saturday, August 12, 2006 2:03 AM
To: sv-bc@eda.org
Subject: RE: [sv-bc] [Fwd: Issues with IEEE 1364-2005]

> Greg Jaxon pointed out to me that it would be more natural to define
> 
>     A ? B   -->   A ?  B : '0
> 
>     A ?: B  -->   A ? '1 :  B

That's pretty, but very scary to me:  I can all too easily imagine
people writing 

  Y = A ? B;

and wrongly assume that they're getting

  if (A) Y = B;


I agree with Doug Warmke that, given the lack of prior definition, it's
hard to see what's bad about mandating short-circuit semantics for &&
and ||.  Programmers who invoke operations with side-effects in such a
context deserve any surprises they may get :-)
--
Jonathan Bromley, Consultant

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