Zugg Software :: View topic

Wizard Joined: 26 Mar 2008 Posts: 1547

Is there a way to see if a certain Variable, Alias, Trigger, Event, etc... exists, not simply whether or not if it's null? I'm in a situation where I have a variable which will be null from time to time and yet, in order to make it work in other scripts which may or may not need it for the script to run, but, will, optionally use if it is there, I need to know if the actual variable exists. Is there any way to do that?

Posted: Sun Jan 16, 2011 3:15 am

Have you tried %defined()? Not sure if it will work for triggers or events. it works for variables I know. %class will work to tell you if just about anything exists if it is nameable. -1 non existent, 0 disabled, 1 enabled.

Wizard Joined: 26 Mar 2008 Posts: 1547

That might do it! ;)

I was looking for a %isexist or %exist, didn't think to check %defined

%class and %trigger exist for both of those. Neato, :)

GURU Joined: 23 Dec 2000 Posts: 4834 Location: USA

%class() and %trigger() are two names for the same function.

Posted: Sun Jan 16, 2011 7:41 pm

Except that %class and %trigger aren't just for class and trigger, apparently. They return true if the parameter is an alias. I wonder if that's a bug, then? :\

Wizard Joined: 22 Mar 2007 Posts: 2320

No, it is not a bug. Originally %class only worked on classes, but that was long ago and far away...or something :) It was deliberately extended to work on all Cmud settings, and the documentation specifically mentions that.

Posted: Sun Jan 16, 2011 8:33 pm

since the help file for both says they work for any "named" setting I wouldn't consider it a bug but that's just me.

Wizard Joined: 26 Mar 2008 Posts: 1547

Since Variables can also have three states: Enabled, Disabled, Non-existent, I feel as though perhaps one function should just be made called exists.

Syntax: %exists(object[, type])

object represents a named setting: Variable, Function, Alias, Class, Trigger, Event, Macro, etc...
type an optional parameter which allows you to narrow searches when you might have more than one of the same name over a couple of different objects, it would be numerical (1-Variable, 2-Alias, etc...)

Returns: 1-Enabled, 0-Disabled, -1-Does not exist

Wizard Joined: 22 Mar 2007 Posts: 2320

Well, %class already works on variables. So, what you are suggesting is essentially an optional second parameter to %class to specify a type, right? There's no reason to change the name of the function, since you would still have to keep the %class function for backward compatibility.

Wizard Joined: 26 Mar 2008 Posts: 1547

%class just isn't a very intuitive name (unless it was just for classes). You could keep class and add the "new" function and sort of transition over to it in a couple major versions.