Would it be a problem for all types in class Elt to have a default or zero value?

[Manuel M T Chakravarty]

> I've run into some situations where it would make it convenient for, say, constructing arrays of default values for a permute (that you know is a proper permutation).

Why do you need default values in a *proper* permutation? (I.e., in that case, you shouldn't need the default.)

I have been thinking about having a "zero" in the past, too, but I never needed it badly. It would probably be ok to have one, though.

Manuel