Re: Union Type Object problem

[Laurence Finston]

On Fri, 13 Aug 2004, Frank Heckenbach wrote:

> That's not really solving linear equations, just plain constant
> arithmetic, with automatic reordering of declarations, or lazy
> evaluation. Maybe it's just this example, though, and it can solve
> linear equations in fact -- does this work?
>
> a = 2b;
> b = a - 3;
> show a;
> --> 6

Yes.  Sorry if my example was bad.

>
> > In MF, `path a' can be a `declaration' or a
> > `boolean expression', e.g.,
> >
> > path a; % `declaration'
> >
> > if (path a) % `boolean expression'
> > ...
> > fi
> >
> > I'm not even going to try to implement this using Bison.  Maybe it would 
> > work,
> > but I think it's so likely not to, that I'm going to just use `is_path', 
> > etc.,
> > for the `boolean expressions' instead.
>
> Since the context it clearly distinct (provided `if' is a keyword),
> this should be no problem at all.
>

I think it might do in other contexts.  For example, I might decide to
allow declarations inside parentheses.  Perhaps I'm being overly cautious,
but I've generally had more problems when I haven't been cautious enough.
I also don't like the ambiguity of type names being declarators in one
context and conditional operators (or whatever one would call them) in
another.

Laurence