Variable Scoping

Mark Smith mark at maseurope.net
Mon Oct 9 12:42:04 CDT 2006


To add to this, and maybe this is not relevant, you can also pass  
parameters by reference, using '@'


on handler1
   put "someText" into someVariable
   handler2 someVariable
   put someVariable
end handler1

on handler2 @someVariable
   delete char 1 of someVariable
end handler2

if you run this, you will see "omeText" in the message box.

This may not what be you want, but can be useful when working with  
variables containing a lot of data, since  the data itself is not  
passed (ie. copied) from handler1 to handler2, which might have  
performance implications where big data is concerned.

Best,

Mark


On 10 Oct 2006, at 01:12, Mark Schonewille wrote:

> Robert,
>
> If you need a variable to be available to all handlers in an object  
> (button, field, card, stack, group) you can do the following:
>
> local lVar
>
> on handler1
>   put x into lVar
>   handler2
> and handler1
>
> on handler2
>   put lVar
>   -- message box contains x
> end handler 2
>
> but if you need the variable only in handler1 and handler2 and not  
> in any other handler of the script of that particular object, you  
> can do
>
> on handler1
>   put x into myVar
>   handler2 myVar
> end handler1
>
> on handler2 theVar
>   put theVar
>   -- msg box contains x
> end handler2
>
> If you want a variable to be available to all scripts in the IDE or  
> standalone, replace
>
> local lVar
>
> with
>
> global gVar
>
> and use the following:
>
> global gVar
>
> on handler1
>   put x into gVar
>   handler2
> and handler1
>
> on handler2
>   put gVar
>   -- message box contains x
> end handler 2
>
> Hth,
>
> Mark
>
> --
>
> Economy-x-Talk
> Consultancy and Software Engineering
> http://economy-x-talk.com
> http://www.salery.biz
>
> Get your store on-line within minutes with Salery Web Store  
> software. Download at http://www.salery.biz
>
> Op 7-okt-2006, om 6:18 heeft Robert Sneidar het volgende geschreven:
>
>> Am I correct in stating that variables in a custom command are not  
>> visible to other commands and functions that it calls? In other  
>> words, if I put "blah" into bobtest in handler "dosomething" and  
>> then "dosomething" calls handler "somethingelse", is bobtest  
>> invisible to handler "somethingelse"? Is there any way to change  
>> this behavior? If not, is there any way I can lobby Runtime  
>> Revolution to consider adding this as a switchable option? OMHO  
>> children should inherit what the parent has. I see variables  
>> defined by a parent as objects belonging to the parent, and  
>> therefore should be visible to the parent.
>>
>> Then the local declaration would have some meaning. Declaring a  
>> variable as local would force the behavior that is status quo now.  
>> Otherwise parent variables would be visible to the handlers the  
>> parent calls. This seems to make more sense to me. But I suspect  
>> this would be a huge recoding change.
>>
>> I think I could mimic this behavior, but at a big performance  
>> penalty. I think my Foxpro port hangs on this.
>>
>> Bob Sneidar
>> IT Manager
>> Logos Management
>> Calvary Chapel CM
>
> _______________________________________________
> use-revolution mailing list
> use-revolution at lists.runrev.com
> Please visit this url to subscribe, unsubscribe and manage your  
> subscription preferences:
> http://lists.runrev.com/mailman/listinfo/use-revolution




More information about the use-livecode mailing list