[Axiom-developer] fixing SPAD

[Martin Rubey]

Dear Gaby & Waldek,

as you may know, there is a problem fixing bug #354, Complex R is not
necessarily a field when R is a field.

It would be quite straightforward to fix it, if we could conditionally export
Field, depending on a Boolean valued function, like

if R has Field and R has Finite and size()$R rem 4 = 1 then Field

Currently, spad seems to accept statements of the form

   D has C

and

   D1 is d2

only.  (Please check this, I'm not entirely sure.)  Do you think it would be
difficult to fix this?  I do not see a workaround, unfortunately.

Many thanks,

Martin