[boost] Re: Expression templates

From: Darin Adler (darin_at_[hidden])
Date: 2000-01-01 20:05:49

> Oops. I just thought about this a little more carefully, and I don't think
> it's possible to make it sufficiently general without a typeof() operator,
> which we don't have. For example, generating a template functor for the
> slightly different expression Elem() + x would require deriving the type of
> the desired result.

But should that prevent you from pursuing this at all? I think that
something that supported:

    element() += 3
    element() += 3 + x
    element() += element()

but didn't support:

    element() = element() + 3

would still be quite useful. And it would be good to identify precisely what
can and can't be done without typeof.

I'd be willing to help complete and refine the expression template, Dave, if
you decide to start on it.

    -- Darin