Re: Value of given type cannot be case to its own type.

[Per Bothner <per@bothner.com>]

On 2/10/21 7:12 AM, J. Vincent Toups via Kawa wrote:
> I'm seeing this error:
> 
> Value 'lib.mecs@131a7516' for variable 'm' has wrong type (lib.mecs)
> (lib.mecs cannot be cast to lib.mecs)
> 
> Which on the face of things is kind of flabbergasting. The specific
> line of code which causes the issue suggests that it is indeed the
> case that the value lib.mecs@etc... is a lib.mecs instance and its
> being used as a lib.mecs instance.

We cannot possibly diagnose this without a test-case.

There are various possibilities.  The one that first comes to mind is a
class-loader problem: There are two classes named lib.mecs, loaded using
two different classloaders, and thus they are incompatible.  Though that
would be more likely to show up at run-time rather than compile-time.

It is also possible that one of the "lib.mecs" is not a reference to
an instance of the lib.mecs class (which would normally be the case), but
some type that the Kawa compiler displays as lib.mecs. Off-hand I can't
think of what that could be, but I would not be surprised to see that.
This could be a Kawa bug, of course.
-- 
	--Per Bothner
per@bothner.com   http://per.bothner.com/