Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!pdn!tscs!tct!chip
From: chip@tct.uucp (Chip Salzenberg)
Newsgroups: comp.lang.c++
Subject: Re: Comparison functions for qsort() and bsearch()
Keywords: Sun, C++
Message-ID: <278A3278.1241@tct.uucp>
Date: 8 Jan 91 20:58:31 GMT
References: <1990Dec26.160636.15566@clear.com> <1991Jan2.191630.18581@Think.COM> <60328@microsoft.UUCP>
Organization: Teltronics/TCT, Sarasota, FL
Lines: 23

According to jimad@microsoft.UUCP (Jim ADCOCK):
>I claim either:
>
>1) Casts from a void* to a pointer to an object of some class already 
>defined are in error.
>or
>2) The definitions given by ARM pgs 67-71 are in error.

From the ARM, page 36 [commentary]:
"ANSI C allows an IMPLICIT conversion from a pointer to |void| to a
pointer to another object type (but not to a pointer to function type
...); in C++ a |void*| cannot be assigned to an object of any type
other than |void*| WITHOUT AN EXPLICIT CAST."  (Emphasis mine.)

So if you _do_ use an explicit cast, you may convert a |void*| to an
object of some class already defined.

If the text of the ARM does not explicitly support this point, then it
would seem there is an oversight in the text.
-- 
Chip Salzenberg at Teltronics/TCT     <chip@tct.uucp>, <uunet!pdn!tct!chip>
       "If Usenet exists, then what is its mailing address?"  -- me
             "c/o The Daily Planet, Metropolis."  -- Jeff Daiell