On Mon, Mar 31, 2008 at 6:40 AM, Brian Spilsbury
> If you were to rename the COMMON-LISP package to the ECL-CL package
> (or whatever), and then place a COMMON-LISP package which used this,
> then you could control what other packages receive when they use
> COMMON-LISP:CLOSE (for example), and GRAY:CLOSE could still use
> ECL-CL:CLOSE for its default case.
My brain must be a bit dense today, but I miss the point. GRAY:CLOSE
only has to be used when defining a method that specializes CLOSE. The
user is free to use CL:CLOSE on a Gray stream: it will simply work.
Let me illustrate it:
(defclass my-stream (fundamental-character-input-stream)
((a-stream :initarg :stream)))
(defmethod gray:close (stream &key abort)
(close (slot-value stream 'a-stream) :abort abort))
(let ((a (make-instance 'my-stream :stream (open "foo.txt" :direction :input))))
(close a)) ; Here, GRAY:CLOSE would also work
Notice that the standard function will work on your stream if you have
specialized the Gray generic function for it. Similarly for
STREAM-ELEMENT-TYPE and other functions. The important point is that
the standard functions only perform a method dispatch when the
argument is a CLOS object, thus avoiding this expesive process for
> I suspect that that might involve changing a lot of strings, though. :)
More than that, it changes the home package of a standard symbol.
> A cheaper option for the implementor is for the user to shadowing
> import gray:close, etc into each package which wants to use it.
This is what I intended to write in the changelog, but probably I was
not clear enough.
Facultad de Fisicas, Universidad Complutense,
Ciudad Universitaria s/n Madrid 28040 (Spain)