Is ReDim an atomic operation?

[irnd]

From my understanding functions called by GUI/Tray events have higher priority, i.e. can pause the execution, of functions called by AdlibRegister, which in turn have higher priority over the main program flow.

My question is: if I'm executing a (lengthy) ReDim operation and a GUI/Tray event is raised, would the ReDim be put on hold until the function linked to the event returns?

Thanks for any feedback.

[guinness]

Did you try?

[irnd]

This code seems to confirm that it's indeed an atomic operation. Also, as soon as ReDim starts and I click on the tray icon, the tray menu takes few seconds to appear which suggests that my event is put on hold until ReDim completes. I was actually looking for an official answer to my doubt.

Global $a[16000000]

For $i = 0 To UBound($a) - 1
  $a[$i] = $i
Next

Opt("TrayMenuMode", 1)
Opt("TrayOnEventMode", 1)

$check = TrayCreateItem("check")
TrayItemSetOnEvent($check, "check")
Func check()
ConsoleWrite("current size = " & UBound($a) & @CRLF)
EndFunc

TraySetState()

Global $init = TimerInit()
ConsoleWrite("initial size = " & UBound($a) & @CRLF)
ReDim $a[15999999]
ConsoleWrite("final size = " & UBound($a) & @CRLF)

[guinness]

It blocks operation whilst redimming is taking place.

Edited February 21, 2013 by guinness

[jchd]

If it wasn't the case, the language would be inconsistent and could very easily crash correct programs. Adlib, OnEvent and friends can only get control once the current statement is complete, this is a fundamental requirement.