[news.eclipse.modeling.mdt.uml2.ocl] Re: How to declare type of empty co

[Tord Alenljung <torda@xxxxxxxxxxx>]

Bug report at https://bugs.eclipse.org/bugs/show_bug.cgi?id=164614

Thanks
Tord

Christian W. Damus wrote:
> Hi, Tord,
>
> The element type of a collection literal is inferred from its contents (as
> the common supertype of its elements, which may be OclAny or
> Collection(OclAny) in mixed cases).  The inferred element type of an empty
> collection literal is OclVoid, which conforms to all other types, so your
> expression (I) should work.
>
> This is a bug.  Would you mind raising it? (on the MDT UML2 OCL component):
>
> https://bugs.eclipse.org/bugs/enter_bug.cgi?product=MDT&version=1.0.1&component=UML2%20OCL&bug_severity=normal&form_name=enter_bug
>
> Thanks,
>
> Christian
>
>
> Ed Merks wrote:
>
> > Tord,
> >
> > I'll forward your question to the new OCL newsgroup.
> >
> >
> > Tord Alenljung wrote:
> > > How can I declare that for example a Set contains objects of some type
> > > and then initialize it to be empty. Neither I or II below works, but
> > > III does.
> > >
> > > (I) Not OK
> > > let a:Set(Integer)=Set{} in a
> > >
> > > 'Init expression type does not conform to type of variable (a).'
> > >
> > > (II) Not OK
> > > let a:Set(Integer)=Set(Integer){} in a
> > >
> > > '1:20:1:31 "collectionTypeIdentifierCS" expected instead of
> > > "Set(Integer)"'
> > >
> > > (III) OK
> > > let a:Set(Integer)=Set{1,3,2} in a
> > >
> > > 2
> > > 1
> > > 3
> > >
> > > Regards
> > > Tord