Path: utzoo!utgpu!water!watmath!clyde!rutgers!cmcl2!nrl-cmf!ames!pasteur!agate!violet.berkeley.edu!edmoy
From: edmoy@violet.berkeley.edu
Newsgroups: comp.sys.mac.hypercard
Subject: Re: XCMD help needed
Keywords: XCMD XFCN states global data
Message-ID: <7105@agate.BERKELEY.EDU>
Date: 22 Feb 88 01:22:00 GMT
References: <515@hscfvax.harvard.edu>
Sender: usenet@agate.BERKELEY.EDU
Reply-To: edmoy@violet.berkeley.edu.UUCP ()
Organization: University of California, Berkeley
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In article <515@hscfvax.harvard.edu> beamlab@hscfvax.UUCP (850103@D.McCallie) writes:
>	Is it possible to write an XCMD that remembers (internally)
>data between invocations ? In other words, can I have states associated
>with an XCMD so that the first call is treated differently from
>subsequent calls ?

I haven't tried it yet, but if you create a resource (say of type 'DATA') in
the stack, then you could do a GetResource() every time your XCMD is called.
By making it nonpurgeable, the data would remain intacted.  The latest state
of the resource could be saved permenently by calling ChangedResource().

>	A similer question: is it possible to have external global
>data that is shared between separate XCMDs, or must I send such
>info back to HC itself (and thus require the stack author to
>create stack "global" variables.

If the XCMDs shared the same knowledge of the resource, then the resource
can be used to pass global info.

Edward Moy
Workstation Software Support Group
University of California
Berkeley, CA  94720

edmoy@violet.Berkeley.EDU
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