The trick here, of course, is that objects are not values - you can
only have a reference to an object as a value, and that reference is
itself a primitive member of the referring object.
Which brings up the issue: how did you lose track of what it was you
were dealing with? If you're building dev tools that's fine. If you're
wanting this for production code, though, you might want to rethink
your approach.
Anyways, ... here's how I'd approach this issue:
isRef=:3 :0"0
try.
0 <: 4!:0 y
catch.
0
end.
)
Thanks,
--
Raul
On Mon, Jul 9, 2018 at 9:41 PM 'Jon Hough' via Programming
<[email protected]> wrote:
>
> I want to test if a given member variable of an object is primitive (e.g.
> one of the J datatypes - literal, integer etc etc) or an object.
>
> coclass 'MyClass'
>
> create=: 3 : 0
> m=: 'something'
> )
>
>
> Here is one method:
>
> myClass =: '' conew 'MyClass'
> a: -: {. (copath ::( a:"_) m__myClass) -. <, 'z' NB. return 1 if primitive,
> 0 if an object.
>
> This works, except if the member is defined in a parent class.
>
> coclass 'MyOtherClass'
> coinsert 'MyClass'
>
> create=: 3 : 0
> create_MyClass_ f. ''
> ''
> )
>
>
> myOtherClass =: '' conew 'MyOtherClass'
> a: -: {. (copath ::( a:"_) m__myOtherClass) -. <, 'z'
>
>
> the above returns 0, but member is a primitive member of the MyOtherClass
> instance. Ideally this
> should return 1 in this case, since m is still a primitive member of
> MyOtherClass.
>
> Any better way to test for primitive members?
>
> Thanks,
> Jon
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