Re: [boost] Re: A couple of issues in submitting typelists to boo st

From: Emily Winch (emily_at_[hidden])
Date: 2001-11-20 06:39:33

> > Yes, but WHY A MACRO?
>
> Ok, I agree in this case one can use super_subclass<T, U>::type (can > you
say "pretty ugly")...

Not half as ugly as ALL UPPERCASE :)

Here is an argument that might be relevant.

SUPER_SUBCLASS is essentially a function operating on types, that takes two
types and returns a type.

Functions are useful for all sorts of things including passing them to other
functions for evaluating later.

Making SUPER_SUBCLASS a macro would remove that option.

At the moment I can't think of a practical situation in which it would be
useful to pass super_subclass as a template template parameter, but it might
be worth keeping in mind. I'm already doing this with things like
boost::is_pointer, for my tuple filter iterator thing.

Emily.