[boost] Re: as_sequence<R(T0,T1)> ?

From: Alexander Nasonov (alnsn_at_[hidden])
Date: 2004-10-11 11:38:50

Jonathan Turkanis wrote:
> "Tobias Schwinger" <tschwinger_at_[hidden]> wrote in message
> > However, I guess you are talking about another as_sequence distinct
> > from
> > mpl::as_sequence...
> 
> Yes, I misunderstood the question. I don't like the idea of
> 'overloading'
> mpl::as_sequence this way, but generating sequences from function
> types vice
> versa seems like a legitimate request. I'm still not sure I see the
> difficulty
> though.
    
Yes, I mean mpl::as_sequence. I know, overloading it this way is not a
best idea but, I can think of mpl::as_sequence only as a sugar. That is,
if template X accepts MPL sequence, you can pass an ordinary type if
X has mpl::as_sequence underneath:

    X<mpl::vector<int> > // 1
    X<int>               // 2 - sugar for 1

Sequence concept is mixed up with ordinary types but if you tell a user
about it, they can accept it.
If mpl::as_sequence treated function types as I suggest, it could
introduce more sugar:

    X<int(char)> // 3 - sugar for mpl::vector<int,char>

but this could confuse a user.

--
Alexander Nasonov