Le mercredi 10 février 2016 à 00:47 -0800, Jeffrey Sarnoff a écrit :
> I want to Typename{T,N} as Abstract onlyif Typename.abstract==true,
> otherwise Typename.abstract==false and I want to treat it as Concrete
>
> Milan's solution displays the subtypes immediately. The way it is set
> up is neat -- but how to pull the targeted type out of the body?
>
> I need this to be a callable function that yields a manipulable tuple
> or vector or tuple of subtuples or etc.
Could you elaborate a bit? Do you need a tuple, or a tuple type?
Regards
> On Wednesday, February 10, 2016 at 3:26:14 AM UTC-5, Tommy Hofmann
> wrote:
> > I think the recursive solution of Milan will give you a finite list
> > of all subtypes. But the list will contain things like Array{T, N},
> > that is, a type with a parameter. How do you handle those? Do you
> > want to count them as abstract or concrete?
> >
> > On Wednesday, February 10, 2016 at 9:10:16 AM UTC+1, Jeffrey
> > Sarnoff wrote:
> > > Hello Tommy,
> > >
> > > OK, putting off inclusion of recursive types ...
> > > and ignoring all possible values for the parameters of a
> > > parameterized type unless already explicitly defined (present in
> > > memory) ...
> > >
> > > allsupertypes(T) should be a short list from T to
> > > supertype(T) to supertype(supertype(T)) .. to Any
> > >
> > > allsubtypes(T) seems obtainable
> > > I can throw things into a tree until the leaves have no
> > > subtypes, then traverse it; is there a nice way to do that
> > > implicitly within a function?
> > >
> > >
> > >
> > >
> > > On Wednesday, February 10, 2016 at 2:32:35 AM UTC-5, Tommy
> > > Hofmann wrote:
> > > > You implicitly assume that a type has only finitely many
> > > > sub/supertypes, which for arbitrary types is clearly not the
> > > > case. The simplest example is Any but you can also get this
> > > > behavior when defining recursive types. More generally, given
> > > > types TL, TU there is no way of returning all types T with TL
> > > > <: T <: TU. You can describe this set using TypeVar, but you
> > > > cannot just write it down.
> > > >
> > > > Tommy
> > > >
> > > > On Wednesday, February 10, 2016 at 12:50:43 AM UTC+1, Jeffrey
> > > > Sarnoff wrote:
> > > > > I see that your definition pours the subtypes from a pitcher
> > > > > of the poured subtypes. The note about parametric types is
> > > > > well pointed. -- Jeffrey
> > > > >
> > > > > Clearly, the answer is therein. Cloudily, I'm looking.
> > > > >
> > > > >
> > > > > On Tuesday, February 9, 2016 at 3:43:48 PM UTC-5, Milan
> > > > > Bouchet-Valat wrote:
> > > > > > Le mardi 09 février 2016 à 12:24 -0800, Jeffrey Sarnoff a
> > > > > > écrit :
> > > > > > > Any advice on quick 'n EZ coding of something like
> > > > > > these?
> > > > > > >
> > > > > > > allsupertypes(Irrational) == ( Real, Number, Any )
> > > > > > >
> > > > > > > allsubtypes(Integer) == ( BigInt, Bool, Signed,
> > > > > > Int128,Int16,Int32,Int64,Int8, Unsigned,
> > > > > > UInt128,UInt16,UInt32,UInt64,UInt8 )
> > > > > > > abstractsubtypes(Integer) == ( Signed, Unsigned )
> > > > > > > concretesubtypes(Integer) == (
> > > > > > BigInt,Bool,UInt128,UInt16,UInt32,UInt64,UInt8,UInt16,UInt3
> > > > > > 2,UInt64,UInt8)
> > > > > > Here's a way to get all concretes ubtypes:
> > > > > > subtypestree(x) = length(subtypes(x)) > 1 ?
> > > > > > map(subtypestree, subtypes(x)) : x
> > > > > > [subtypestree(AbstractArray)...;]
> > > > > >
> > > > > > You should be able to adapt this to return all abstract
> > > > > > types instead
> > > > > > by using isleaftype() (which would better be called
> > > > > > isconcretetype()?).
> > > > > > But note there's the special case of parametric types,
> > > > > > which aren't
> > > > > > leaf types.
> > > > > >
> > > > > >
> > > > > > Regards
