Reading and writing globals by script
ahsoftware at sonic.net
Sat Aug 10 21:21:27 EDT 2019
On 8/10/19 12:00 PM, David Epstein via use-livecode wrote:
> I want to write a function that will read and write to any named global. What I have below seems to work, but I’m not sure quite why. Usually, “put gName into oldVal” for a global named gName would put the value, not the name, of that global into oldVal. But here it does not.
> function globalSwap gName,gVal
> -- Return the existing value of global gName and load gVal into that same global
> do "global" && gName
> do "put" && gName && "into oldVal" # "put gName into oldVal" doesn't work here.
> do "put gVal into" && gName
> return oldVal
> end globalSwap
> Is there some way to write this with fewer or no uses of “do”?
Well, the best way, of course, is not to use globals.
Barring that (watch the wordwrap),
function globalSwap gname, pVal
local tOldVal, tCommand
tOldVal;put"&&pVal&&"into"&&gName into tCommand
ahsoftware at gmail.com
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