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From: 880716a@aucs.uucp (Dave Astels)
Newsgroups: comp.lang.c++
Subject: Zortech C++ 2.1
Message-ID: <1990Aug26.152705.10927@aucs.uucp>
Date: 26 Aug 90 15:27:05 GMT
Organization: Acadia University - School of Computer Science
Lines: 57


I recieved my upgrade to 2.1 recently.  Looks like a great product so far.
ZWB is a definite step up (read LEAP) from ZED.  The browsers are neat.
One problem:  with a Hercules card, the mouse cursor is invisible if not
on top of text i.e. it doesn't show when over a blank.

Something else.. not a problem, just something that confused me for a while:
code that worked in 2.06 didn't with 2.1.  The situation is the destructor
of a class with two ancestors.  The relavent details are:

class X {
public:
    virtual ~X () {}
}

class Y {
public:
    ~Y ();
}

class Z : public X, public Y {
public
    ~Z () {};
}

This is what happens:  I want to destruct a Z, seeing it as an X.

i.e.:

	void foo (X * bar)
    {
        delete bar;
    }

	void snafu ()
    {
        Z * zzz = new Z;
        foo (zzz);
    }

The idea is that the call to ~X will turn into a call to ~Z (~X
being virtual), which will cause ~X to call ~Y (which is the important
bit .. Y contains dynamically allocated storage).

The above declaration of Z worked in 2.06, but not in 2.1.  I have to
make the ~Z method non-inline in order for the linker to work.  With ~Z
inline, it complains about ~Z not being found .. i.e. the compiler (I
hope you're listening, Walter) seesm to loose it. 

I don't know if this behavior is to be expected on C++ 2.0 or not (my
copy of E&S is still on order!).

-- 
"I liked him better before he died" - McCoy, ST V
===============================================================================
Dave Astels            |  Internet: 880716a@AcadiaU.CA
PO Box 835, Wolfville, |  Bitnet:   880716a@Acadia