🚀 go-pugleaf

smeyers@netcom.com (Scott Meyers) writes:

>A few months ago there was a discussion of whether the language should be
>extended so that const and non-const objects would have different
>constructors, the idea being that initialization for a const object might
>be different from initialization for a non-const object.  My understanding
>is the committee has rejected that idea.  Could someone please post a
>summary of the problems with the idea or point me to a place where I can
>find them?

One immediate problem is that to do it right would break backwards
compatibility, because you should not be able to invoke a non-const
constructor for a const object, just as you can't invoke a non-const
member function for a const object.  Code such as

	struct X { int a; X(); };
	const X x;

would have to be declared illegal, to be replaced with

	struct X { int a; X() const; };
	const X x;	      ^^^^^

Breaking backwards compatibility like this would be a real problem.

There are other problems (e.g. initialization of arrays may become
very tricky) but I think the above problem would be sufficient to kill
the proposal.

--
Fergus Henderson             	WWW: http://www.cs.mu.oz.au/~fjh
fjh@cs.mu.oz.au              	PGP: finger fjh@128.250.37.3
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