Test Variable?

Jim Ault JimAultWins at yahoo.com
Fri Feb 10 19:35:47 EST 2006


On 2/10/06 3:37 PM, "Phil Davis" <davis.phil at comcast.net> wrote:
 
> When you declare a global within a handler, the data that goes into it
> will stay there, but no other handler can access it - the place where
> you declare a variable determines its scope. Put the "global" statement
> at the top of your script, outside of all handlers; then all handlers in
> that script can access it.
> 
> If your 'openField' handler is in a different script (like of a field),
> then that script will also need to contain a "global varCmdLineParamIn"
> statement for the var to be accessible there.

Actually, 
* no other handler can access it * is not correct.
Declaring a global anywhere creates it in the Rev app.  It is live until you
quit Rev or do "delete global gComputerName"

--example
on doThisStep
  global gComputerName
  put "Fred" into gComputerName
end doThisStep

--at this point, the Rev app has control over the global gComputerName and
any stack or handler can access this global by doing

on buildMyString
  global gComputerName
  put "Working on " & gComputerName into stringToWrite
end buildMyString


Declaring the global in any handler will give that handler access to it.
The confusion comes in when you consider that the following:

--top of stack script
global gComputerName

--now means that any handler in this script has access to the global without
having to declare it.  Of course, declaring it again in a handler makes it
appear in the Variable Watcher twice (or more in 2.6.1 Mac) so you should
only declare the globals one time.

Hope this helps

Jim Ault
Las Vegas





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