Re: AppleScript

[bill@cambridge.apple.com (Bill St. Clair)]

>Date: Fri, 22 May 1992 14:47:06 -0500
>To: Bruce Lester <72110.1107@CompuServe.COM>
>From: bill@cambridge.apple.com (Bill St. Clair)
>Subject: Re: AppleScript
>Cc: info-mcl
>
>>Will the new version of MCL 2.x support AppleScript?
>
>No, MCL 2.0 will not support AppleScript. AppleScript was vaporware
>when MCL 2.0 was being developed.
>
>Future versions will support it as much as is possible. From what little
>I know about AppleScript it calls application provided callbacks
>asynchronously. If this is true, it will be difficult to support in MCL.
>You will need to write the callbacks either using the foriegn function
>interface or with a subset of Lisp that is very careful not to call
>anything that is not reentrant or likely to be inaccessible because
>the garbage collector is running. This is the reason that interrupt
>routines cannot be written with DEFPASCAL.

Some people here have reminded me that I said a bit too little about
this. MCL 2.0 will at least minimally support AppleScript in that it
allows you to write AppleEvent handlers. I believe that the callbacks
that AppleScript does are to enable it to parse application-specific
AppleScript syntax. These do not happen completely asynchronously, but they
do happen when MCL is not the current application. MCL will be able to
handle these only if you turn off event processing during garbage collection:

      (set-gc-event-check-enabled-p nil)

This is NOT the default.

MCL 2.0 does not have any high level AppleScript specific support.
I will add this to the ever-growing list of desired MCL 2.1 features
(or maybe one of you will do it and make it available to the community).