User Extensions/Externals

J. Landman Gay jacque at
Mon May 3 13:06:50 EDT 2010

Graham & Heather Harrison wrote:

> Whether ssMacWindows has a problem with rev 4.0.0, or Mac OS X 10.6.3
> I can't say, and I have not found a way to contact Shao Sean; there
> is no link on his web site. Can anyone help me with contact
> information, or who best to ask at Rev?

She reads this list so you've probably done the right thing by asking here.

> Jacque, you said that externals were difficult, and that there is a
> (steep) learning curve for rev.

Well, I said I it wasn't *that* hard, but not something I'd jump into 
right off while still learning Rev basics.

> That is proving true for  me because
> I am using the latest version of rev, on the latest Mac OS X. I am
> finding that the documentation, examples and lessons are written for
> older OS's and older rev's. In fact I would not be surprised if was
> easier to learn rev on a G5 PPC running Tiger (or Leopard perhaps),
> and a previous release of rev.

I don't think so. As far as I know, nothing's changed in the way 
externals work in years. There have been some new ways of forcing them 
to load ("new" as of a few years ago,) but the underlying principle of 
it is the same as always: externals only load when a stack is first 
opened, and the path to the external must be correct. Now how you manage 
that can be done several ways, from simple to complex, but they all do 
the same thing in the end.

> But putting that aside, I have long
> held the opinion that you can't know a program properly until you try
> to fix it when it goes wrong, so this has been an excellent learning
> experience, and the curve has flattened out a
> tad.

That's good. To me, it seems a little backwards, like learning addition 
by figuring out multiplication, but I guess everyone has their own 
method. I'd have done it the other direction. To use externals it's good 
to have some basic info under your belt about Rev's messaging order, 
default directories, destroystack behavior, how unopened stacks are held 
in memory (or not), relative and absolute file paths, and so forth.

I haven't used the ssMacWindows external yet but I'll try it just to see 
what you've been up against. I am fairly certain it can't be much 
different than any of the others, since there's really only one way to 
load an external in spite of the several methods you can take to get there.

Jacqueline Landman Gay         |     jacque at
HyperActive Software           |

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