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Re: How to see if variable is defined? [message #3357]

Sat, 21 January 1995 10:22

ps
Messages: 14
Registered: September 1994

Junior Member

Ralph Finch (rfinch@water.ca.gov) wrote:
: Is there a nice way of checking if a variable is defined?

: I have a widget_control command which removes a menu, and I need to
: see if the menu is defined before destroying it.
: --
: Ralph Finch 916-653-8268:voice 916-653-6077:fax
: rfinch@dop.water.ca.gov / finger for PGP public key
: "Nada burra la chamaca." A.G.
: Any opinions expressed are my own; they do not represent my employer

examine size(var). if s(s(0)+1) equal zero, var is undefined.
Or try the function keyword_set. But it has some problems if the
variable to be examined is zero.

Peter

------------------ Peter 'PIT' Suetterlin -----------------
| Kiepenheuer Institut | Sternfreunde Breisgau e.V |
| fuer Sonnenphysik | |
| 0761/3198-210 | 0761/71571 |
-<ps@kis.uni-freiburg.de>-<suettpet@sun1.ruf.uni-freiburg.de>--

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		Re: How to see if variable is defined? By: ps on Sat, 21 January 1995 10:22
		Re: How to see if variable is defined? By: rivers on Sat, 21 January 1995 09:04

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