Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!bellcore!salt!stanm
From: stanm@thumper.bellcore.com (Stan Moyer)
Newsgroups: comp.lang.c++
Subject: Re: constructor as default argument
Message-ID: <443@salt.bellcore.com>
Date: 12 Jun 91 18:01:23 GMT
Sender: news@salt.bellcore.com
Lines: 53

In regards to my earlier posting, I've learned the following:

This piece of code:

	#include <stream.h>

	class X {
	public:
		X(int i) { cout << "X(int): " << i << "\n"; }
	};

	const int DEF_X = 0;

	class Y {
	public:
		Y() {}
		void f(X x=0) {}
		void g(X x=X(0)) {}
		void h(X x=DEF_X) {}
	};

	main ()
	{
		Y y;
		y.f();
		y.g();
		y.h();
	}

compiles and produces the following output with g++:

X(int): 0
X(int): 0
X(int): 0

However, when I try to compile with cfront, I get the following output:

	line 13: sorry, not implemented:  constructor needed for argument 	initializer
	line 14: sorry, not implemented:  constructor as default argument
	line 15: sorry, not implemented:  constructor needed for argument 	initializer
	
I have learned that "sorry, not implemented" does not mean that there is
an error, but rather "this is probably valid C++, but we haven't
implemented it in the compiler." Hopefully a future version (3.0?) of
cfront will implement this, but until then I'll have to work around it.

Thanks to Martin Hitz and Brian Kennedy for their responses.

Stan Moyer

<stanm@thumper.bellcore.com>; Bellcore, MRE-2A219;
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