Some other oddities

[Sean Luke <sean at cs dot gmu dot edu>]

Thanks for stomping the class bug; turnaround time isn't crucial, as  
I've got a hack that gets around it for now.  And I'm SHOCKED at the  
speed Kawa's running my examples when you load it down with type  
declarations.  About 1.5 the speed of full, reasonably optimized  
Java.  Really amazing!

A few other oddities I came across in Kawa that I can't find answers  
to in the docs.  Could anyone shed some light onto them for me?


0. The syntax for making multidimensional arrays is lacking.  To do  
this in Java:

    public static final int[][] b_heptomino = new int[][]
    	{{0, 1, 1},
    	 {1, 1, 0},
	 {0, 1, 1},
	 {0, 0, 1}};

The best I've been able to manage is:

    (b-heptomino type: <int[][]>
        allocation: 'static
        init-form: (make <int[][]>
                    (make <int[]> 0 1 1)
                    (make <int[]> 1 1 0)
                    (make <int[]> 0 1 1)
                    (make <int[]> 0 0 1)))

Yuck.  Still, a big improvement over 1.8.



1. The documentation says that to access fields defined in Scheme in  
a simple-class, you have to use (slot-ref foo 'bar), but for standard  
Java classes you can use (#:.bar foo).  And it appears to be the case  
in my testing.  :-(  The question is: why is this the case?  It sure  
makes for an inconsistent user experience.



2. Load order for mutually-referential simple-classes seems to be  
broken, or at least inconsistent in an undocumented way.  I have a  
class called <tutorial1> which has a method that looks like this:

	(define-simple-class <tutorial1> (<sim.engine.SimState>)
		((start) :: <void>
			..........
			(make <ca>) ....

I have another class called <ca> which has a method which like this:

	(define-simple-class <ca> (<sim.engine.Steppable>)
		((step (state :: <sim.engine.SimState>)) :: <void>
			..........
			(let ((tut :: <tutorial1> (as <tutorial1> state))) ....

As can be seen, they each refer to the other.  If you load  
<tutorial1> before <ca> you get a warning:

	(load "tutorial1.scm")
	(load "ca.scm")
	
		tutorial1.scm:40:13: warning - unknown class: ca

... and it works fine.  But if you load ca first before loading  
tutorial1, kawa spits out a large Java error indicating that  
tutorial1 doesn't exist yet!  Specifically:

	(load "ca.scm")
	
		ca.scm:13:36: unknown class: tutorial1
		java.lang.RuntimeException: no such class: tutorial1
		        at gnu.bytecode.ObjectType.getReflectClass(ObjectType.java:77)
		        at gnu.bytecode.ClassType.addFields(ClassType.java:402)
		        at gnu.bytecode.ClassType.getFields(ClassType.java:306)
		        at gnu.bytecode.ClassType.getDeclaredField(ClassType.java:320)
			........
		Caused by: java.lang.ClassNotFoundException: tutorial1
		        at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
		        at java.security.AccessController.doPrivileged(Native Method)
		        at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
		        at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
			........

What's failing, and why?  Is it the tut :: <tutorial1> that requires  
tutorial1 exist?  or is it the case (which, btw, appears to be  
NECESSARY if I want to call a function on the tutorial1 method that  
doesn't exist in its superclass -- very un-scheme-like :-(  )