Re: Tuples Library Formal Review

From: jaakko.jarvi_at_[hidden]
Date: 2001-06-20 05:43:37

--- In boost_at_y..., "Vesa Karvonen" <vesa.karvonen_at_h...> wrote:
> > > - Would it be useful to have a clearly specified and documented
> > > metaprogramming interface for creating and accessing tuples?
<snip>
Basically adding a few typedefs and documenting them.
Ok, this can be done and is a good idea.

> > > Additional comments
> > > ===================
> > >
> > > Lexicograhical ordering is not the only useful ordering model. 
Other
> > > frequently useful models include:
> > > - ordering based on only a subset of elements (e.g. key-value 
pair)
> > >   - note: std::map<K,V>::value_type suffers from this problem
> > >   - for this reason, I use neither tuple nor pair in my 
container
> > library.
> > > - dominance:
> > >     A<B if a(i)<b(i) for all i

I did think of alternative orderings, but ended up with the conclusion
that lexicographical ordering is probably the most useful (though not
the most natural one from a mathemathical point of view)

Vesa's point about the virtues of small headers made me think
that maybe comparison operators should be in a separately includable 
file.

/Jaakko