Re: get variables name

[davidf(at)dfanning.com (David Fanning)]

R.Bauer (R.Bauer@fz-juelich.de) writes:

> I like to know the name of a variable which is submitted as input to a
> procedure
> 
> e.g
> 
> pro test,var
> help,var
> end
> 
> a=1
> test,a
> 
> Is it possible to get inside test the information that test was called
> with a.

My life is totally out of control at the moment, so I haven't
had the opportunity to write this up for my web page, but
here is part of a correspondence I recently received from
Paul Woodford, an IDL user, concerning the undocumented
ROUTINE_NAMES function:

   routine_names(variables=0) - variable names at current level
   routine_names(variables=1) - variable names at main level
   routine_names(variables=2) - variable names at one level down from main
   routine_names(variables=-1) - variable names at one level up from current
   routine_names(variables=-2) - variable names at two levels up from current

   But wait, that's not all...  Take a look at how routine_names is used in
   gethelp - you can use routine_names to actually fetch a variable from a
   different level.  For instance, if you have a variable named 'blah' one
   level up from your current level, you can get it using

   blah_here = routine_names('blah', fetch=-1)

Now, I would add a STRONGLY worded caution here. This routine is
COMPLETELY undocumented. I suspect there is a reason for that.
When you write your program relying on this behavior, and RSI 
changes it in the next release (which is their prerogative with
a COMPLETELY undocumented function), then I don't want to hear
any whining! :-)

Cheers,

David

-- 
David Fanning, Ph.D.
Fanning Software Consulting
Phone: 970-221-0438 E-Mail: davidf@dfanning.com
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