Re: Problem using MyType[] in macros

[Bill Robinson <airbaggins at gmail dot com>]

Hello.

I have just spent the evening reducing my original code down, and
perhaps this is a bug. I can't work it out:

test.macro.scm:
(define (my-helper field-op-expr)
  (syntax-case field-op-expr (array int pack java-type)
    (((array subtype) java-type)
     (with-syntax ((sub-java-type (my-helper (syntax (subtype java-type)))))
		  (syntax (different-thing sub-java-type))))
    ;; THIS NEXT CASE is messing things up! commenting it out fixes it
    (((array subtype) pack another another2) (syntax ()))
    ((field-type java-type)
     (syntax field-type))))

(define-syntax my-macro
  (lambda (class-def)
    (syntax-case class-def ()
      ((_ field-declaration)
       (with-syntax ((out (my-helper (syntax (field-declaration java-type)))))
		    (syntax (display (format "~A~%" 'out))))))))

test.scm:
(my-macro (array int))

Then I'm compiling with:
$ kawa -f test.macros.scm --main -C test.scm && java -cp
.:/usr/local/share/java/kawa.jar test

This is the result I'm getting:
(compiling test.scm)
test.scm:2:1: evaluating syntax transformer 'my-macro' threw
java.lang.ArrayIndexOutOfBoundsException

This is what I get if I comment out that unrelated syntax-case entry:
(compiling test.scm to test)
(different-thing int)

Investigating further with Eclipse's debugger, SyntaxPattern.allocVars
is getting called with varCount = 2 and outer being an array of 8
long, so outer and it's 8 entries don't fit into the new vars array.
The variable outer is [(int), null, null, null, null, null, null,
null] in the debugger.

Hope this helps.
Thanks!
-Bill