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From: steve@taumet.com (Stephen Clamage)
Newsgroups: comp.lang.c++
Subject: Re: Parentheses after new
Message-ID: <420@taumet.com>
Date: 24 Aug 90 16:32:28 GMT
References: <1619@m1.cs.man.ac.uk>
Distribution: comp
Organization: Taumetric Corporation, San Diego
Lines: 31

jk@cs.man.ac.uk (John Kewley ICL) writes:

>The following fails to compile on both G++ and Sun C++. Could you tell me
>why the brackets around new's argument is illegal....
>class test
>{
>public:
>	test(int eek);
>	test();
>};
>int main()
>{
>	test* thattest= new (test);
>	test* thistest= new (test(1));
>}

The keyword _new_ may be optionally followed by a placement expresion-list
in parens, followed by either a type-name in parens or a new-type-name not
in parens.  If there is no placement, _new_ must be followed by a
new-type-name or by a type-name in parens.  Finally, an initializer-list in
parens may be tacked onto any of these.

So the outer-level parens in a _new_ clause are not part of any expression,
but part of the _new_ syntax to determine which form is being used.  The
examples you have do not fit any of the syntax productions.
-- 

Steve Clamage, TauMetric Corp, steve@taumet.com
-- 

Steve Clamage, TauMetric Corp, steve@taumet.com