Re: [Axiom-developer] A curious algebra failure

[Gabriel Dos Reis]

Martin Rubey <address@hidden> writes:

| Gabriel Dos Reis <address@hidden> writes:
| 
| > As you suggested, I suspect it should have been written like
| > 
| >      if S has SetCategory and S has "*"
| > 
| > The trouble is that we don't want to test just for the name "*".  We
| > want to test for the signature
| >           
| >           "*":(%, %) -> %
| > 
| > I don't know how to write that in Spad -- Ralf?
| 
| I do not know whether it is helpful, but I wrote code like
| 
| diffDSF: DIFFSPECSF
| diffDSF(s, n) == 
| -- I have to help the compiler here a little to choose the right signature...
|     if SUP F has _*: (NonNegativeInteger, SUP F) -> SUP F
|     then D(s, n)
| 
| I don't think that 
| 
|     if S has _*: (%, %) -> %
| 
| would work, but
| 
|     if S has _*: (S, S) -> S
| 
| should.
| 
| Warning: I didn't check whether this is what you want to fix your bug.

That might help.  Let me test Jurgen's fix, first.


-- Gaby