returning a PROXY

Same story as

http://sourceforge.net/mailarchive/message.php?msg_name=18925.45196.206073.901800%40zaphod.home.loc

This time it's more generic as SBCL complained about a null
tree-view-column as return value, which is handled with a proxy.

Here is a patch for what it is worth:

*** proxy.lisp.~1.10.~	2008-05-06 11:00:51.000000000 +0200
--- proxy.lisp	2009-05-06 13:38:14.000000000 +0200
***************
*** 346,351 ****
--- 346,356 ----
    (declare (ignore type))
    (alien-type 'pointer))
  
+ (define-type-method return-type ((type proxy))
+   (declare (ignore type))
+   ;; ensure-proxy-instance may return NIL if pointer is null
+   (return-type `(or ,type null)))
+ 
  (define-type-method size-of ((type proxy) &key inlined)
    (assert-not-inlined type inlined)
    (size-of 'pointer))

-- 
walter pelissero
http://www.pelissero.de

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