Introduced destructors and finalized GdkCursor

[Marko Rauhamaa <marko at pacujo dot net>]

Summary: Introduced destructors and finalized GdkCursor.

Details:

 - build-guile-gtk-1.2: The defs files didn't specify destructors.
   Instead, the garbage collector was trusted to release resources. This
   is the right strategy as long as the resource is a piece of client
   RAM. However, we must release X server resources as soon as they are
   no longer needed.

   I have now introduced a new option for define-boxed and
   define-struct: (physical #t). When set, the function specified in the
   free option becomes callable from guile code. The proxy object stays
   alive, but any reference to it causes an assertion to fail.

 - gdk-1.2.defs: As a first application of destructors, I added the
   (physical #t) option to GdkCursor.


Marko

-- 
Marko Rauhamaa      mailto:marko@pacujo.net     http://pacujo.net/marko/