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Re: Can this be done using CALL_FUNCTION?

Ed Meinel (edward.s.meinel@aero.org) writes:

> No, I'm not too scared... I usually like to wait one major upgrade
> before starting to use a new capability. This gives RSI a chance to fix
> all the bugs that David found ;-) 

Well, that's probably good advice. The only trouble with it is that
if everyone follows it no bugs are found or fixed. :-(

> How many of you started using the HANDLE_* routines as soon as
> IDL4 came out?

It is funny how these things evolve. I don't think handles
would have happened at all, except that I started to advertise
that I could teach people how to use "pointers" in IDL classes.
We were using the user value of unrealized base widgets as
pointers or handles. I remember being surrounded by a bunch
of developers in the hallway once. They had one of my brochures
and they were in an ugly mood. "What the hell is this pointer
nonsense, Fanning?", they demanded.

"Uh, well, they aren't *really* pointers, but look what we
can do with them", I said. Next thing I knew we had an
unrealized base widget with everything stripped off it 
except the user value and renamed a "handle". And, of course,
since that really didn't do *exactly* what we wanted either,
we soon had real pointers. (Well, as real as you are likely
to get in a language like IDL.)

But I do like the direction the language is evolving in.
I just wish they wouldn't make such a big mystery of all
the new object graphics capabilities. I just can't figure
why they want to hide this light under their bushel basket.
I'd be telling the whole world about it. Especially those
young pups who think Matlab is the cat's meow.



David Fanning, Ph.D.
Fanning Software Consulting
Phone: 970-221-0438 E-Mail: davidf@dfanning.com
Coyote's Guide to IDL Programming: http://www.dfanning.com/
Toll-Free IDL Book Orders: 1-888-461-0155