Re: [Axiom-mail] Type of Expression Problem

[Martin Rubey]

Hans Peter Würmli <address@hidden> writes:

> Hi
> 
> What are my wrong expectations in the following interpreter session when 
> using 
> "typeOf" and "has"
> 
> (1) -> e:=(1+n)/(n+k)
>         n + 1
>    (1)  -----
>         n + k
>                                            Type: Fraction Polynomial Integer
> (2) -> typeOf e
>    (2)  Fraction Polynomial Integer
>                                                                  Type: Domain
> (3) -> typeOf (e) has Fraction Polynomial Integer
>    (3)  false
> 
> In (3) I would expect true.

Axiom is correct. "A has B" tests whether the Domain or Category A is a member
of *Category* B or satisfies the axiom B. So 

Fraction Polynomial Integer has Ring

or

Field has Ring

would return true, similarly

PF 5 has commutative("*")

returns true.

Martin