[Grace-core] Numbers and structural typing

[Marco Servetto]

Hi Kim, that solve the first  part of my doubts, but not the second, that is:
The brand would just be a label, actually stored in a field, right?
thus an object may declare to be of any brand in the untyped version.
what happen then? it must be well defined, since type system is just a
dialect, and that definition must be about objects, method and field,
because in grace there is nothing else.

I do not see how a number object in grace can for sure recognize
another number object in the first place.