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From: rvadnais@pyramid.pyramid.com (VadGuy)
Newsgroups: comp.lang.c++
Subject: Re: another Zortech bug?
Summary: It's not a bug
Keywords: Stroustrup
Message-ID: <9002102248.AA09963@polyslo.CalPoly.EDU>
Date: 10 Feb 90 22:48:18 GMT
References: <4800083@m.cs.uiuc.edu>
Sender: daemon@ucbvax.BERKELEY.EDU
Reply-To: rvadnais@pyramid.pyramid.com (VadGuy)
Distribution: usa
Organization: Cal Poly San Luis Obispo
Lines: 38

In article <4800083@m.cs.uiuc.edu> rchen@m.cs.uiuc.edu writes:

>I'm running Zortech 2.0, and possibly the problem is in the
>compiler, but since the details of how to do this don't seem
>to be discussed anywhere, I'm not yet ready to point the
>finger in Walter's direction.
> 
>The problem is to do with static members in a class, where
>the static member is 1) an array; and 2) a user-defined
>class with a single constructor which takes no parameters.
 
[specific example of problem deleted]

We recently ran into this same problem recently in our C++ class.  Here's
what my professor had to say about it:

   From cstaley Wed Feb  7 11:26:37 1990
   Here are two fun facts I've learned about C++:
   ...
   2.
   Buried deep in the innards of Stroustrup is this little rule that says that
   objects that have a constructor may not be used as static data members of a
   class.  This means that you may not have the associative_array as a static
   member of Id, even though this would be stylistically correct.  I can think
   of no reason for this dumb rule, but I didn't design the language. 

I got around this limitation by declaring a null pointer to the
associative_array and then calling the constructor explicitly in 
the constructor for Id when the pointer has a null value.  This requires
the overhead of a check everytime the constructor for Id is called, but 
it does the trick.

In other words: it's not a bug, it's a feature. :)

Hope this helps.
---
Bob Vadnais                              rvadnais@polyslo.CalPoly.EDU
"Have a nice day!"               (Offer void where prohibited by law)