Where Rev could be going...

Bernard Devlin revolution at knowledgeworks.plus.com
Fri Nov 24 08:02:24 EST 2006

Richard Gaskin said:
One of the hardest things in making a browser plugin is dealing with the
limitations of the environment:  no file I/O, no Apple events, no
Registry access, no windows, no window styles, etc.  In a comprehensive
superset of HyperTalk like SuperTalk and Transcript, doing that many
IFDEFs across the code base is a lot of work (and characterizing the
work as simply IFDEFing is of course a generously lighthearted metaphor
for the true nature of the rework).

Hi Richard,

Thanks for those comments.  I think they give us something to think  

I want to continue this discussion a little further to see if my  
understanding is correct: 1) any Rev app that would run in a browser  
plug-in could only offer a sub-set of Rev functionality 2) there  
would need to be a lot of conditional coding in the engine to check  
which environment the code was running within, in order for the plug- 
in to know what it could and could not attempt to do.

The former set of limitations is not that different from Rev running  
in secureMode.  The Dictionary says:

If the secureMode property is set to true, the application cannot use  
the get, put, open file, read from file, or write to file commands to  
gain access to local files. The application cannot run programs with  
the shell function, the open process command, or the  launch command.  
On Windows systems, it cannot use the deleteRegistry, queryRegistry,  
or setRegistry functions to access the Windows system registry.

So, we already have that concept of a player application with limited  
functionality.  That looks to me like the engine already contains  
conditional processing for secureMode.  I'm wondering if this browser  
plug-in couldn't be done as an extension of secureMode.  However, if  
we could make explicit what all the different limitations would be,  
then maybe the advocates of a plug-in will conclude that it is not  
something they would find particularly useful (e.g. if it meant they  
had to code a different version of their app to work with a browser  
plug-in.)  I'm still ambivalent about it myself.

The additional limitations you mention are things like the absence of  
windowing. It would be good if those more experienced developers  
(either pro or con the browser plug-in) could give some thought to  
what the other limitations might be.  One thing I can imagine  
(although I could be way off base here), is that since Rev relies on  
being able to grab more and more memory as the data/resources in a  
stack increase, maybe that too would be a limitation (browsers might  
well try to limit how much memory a plug-in is trying to allocate in  
the name of the browser).


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