Re: [boost] Re: char[] support in Boost.Range

From: Pavol Droba (droba_at_[hidden])
Date: 2005-05-16 15:53:39

On Mon, May 16, 2005 at 12:32:56PM -0700, Eric Niebler wrote:
> 
> Pavol Droba wrote:
> >On Sun, May 15, 2005 at 08:17:15PM -0400, David Abrahams wrote:
> >
> >>"Thorsten Ottosen" <nesotto_at_[hidden]> writes:
> >>
> >>
> >>>|  I'd like to leave it for the discussion. Right now it seems, that
> >>>|  most of the people that entered discussion prefer c-array view.
> >>>|  I would prefer c-string view, but I'm probably biased by the fact
> >>>|  that I'm the author of StringAlgo library.
> >>>
> >>>I prefer the string view too.
> >>
> >>I just have one thing to say: vector<bool>.
> >>
> >
> >
> >Pardon me, but somehow I cannot figure out the point here. Can you please
> >explain the me the connection to vector<bool>
> >
> 
> 
> vector<bool> creates all kinds of problems because generic code can't 
> make assumptions about the behavior of vector<T>. vector<bool> is widely 
> regarded as a Bad Move. Dave is saying that treating char[] different 
> than, say, int[] is inviting the same sorts of problems. It will make it 
> difficult to deal with T[] in generic code.
> 
> I agree with Dave.
> 

I see now what do you mean. I understand this problem and therefor I have
suggested a solution that can work regardless to decision taken here.

But allow me to mention another similarity. There is well knows 'C' idiom, that
char[] is generaly char*. For char* we can only provide c-string handling.
Therefor it brings also a confusion if char[] will be threated differently.
Yet this is probably no as strong as similarity between generic T[] types.

* * * * * * * * * * *

But I see, that this discussion is starting to circle around and it is time to stop it.
There was no objection to the solution I have proposed, so I take it for granted, that
it is acceptable. 
For the default behaviour, we can favor either syntactic (T[]) or semantic (char*)
similarity. Because syntactic similarity is usualy stronger, let's stick with this one.

In addition I would suggest to remove direct support for pointer types like char* from 
the range library and provide it only via as_string() construct to definitely remove
any kind of confusion.

If there are any complaints/suggestion/comments do not hessitate to bring them on.

Best Regards,
Pavol.