Re: [boost] Re: in/out parameters, codingstylesandmaintenance

From: Floris van den Berg (flvdberg_at_[hidden])
Date: 2003-05-04 10:36:23

----- Original Message -----
From: "Noel Yap" <Noel.Yap_at_[hidden]>
To: "Boost mailing list" <boost_at_[hidden]>
Sent: Sunday, May 04, 2003 4:47 PM
Subject: Re: [boost] Re: in/out parameters, codingstylesandmaintenance

> Gregory Colvin wrote:
> >
> > I don't see the point of providing this
> >
> >     void SetArea(c_out<CShape> s)
> >     {
> >             CShape &ls = s.get_ref();
> >             ls.SetArea(100);
> >     }
> >
> > and then writing this
> >
> >     SetArea(out(psq));
> >
> > instead of just writing this in the first place
> >
> >     psq->SetArea(100);
>
> I think a larger point that should be emphasized is that noone so far
> has been able to come up with a function that takes an out parameter
> that cannot be rewritten to return a value.  IMHO, it makes sense to do
> so stylistically.
>
> I can understand some rationale for c_in and c_in_out, but not for
> c_out.

I think that c_out is practically the same as c_in_out, only with c_out the
called function doesn't care about the initial value of the passed
parameter.

Floris