OpenEuphoria

Re: Win32lib, bitmapped captions, David C.

• Posted by JJProg at CYBERBURY.NET Sep 03, 1999
• 697 views

EU>I'd implemented a solution like Hendirk's before, but there's a reason I
EU>never posted it: it was buggy. Not in itself, but in conjunction with calls
EU>to Windows. For example:

EU>   globalVariable = 123
EU>   sendMessage( ... )
EU>   ? globalVariable

EU>What value will be in globalVariable? You can't say, because sendMessage()
EU>causes an immediate callback to WndProc, and there's no guarantee what's
EU>been done to the global variable. I found this out the hard way tracking
EU>down some bugs in Llama. And virtually any Win32Lib routine is a wrapper
EU>around sendMessage(). This is why the getSelf() function is flakey.

EU>Comments?

EU>-- David Cuny

What if globalVariable was a sequence - like a stack. For example:

sequence returnStack
integer returnStackIndex
returnStackIndex = 0
returnStack = {}
global procedure setReturnValue(atom value)
        returnStack[returnStackIndex] = value
end procedure
global procedue WndProc(...)
        atom returnValue
        ...
        returnStack &= 0
        returnStackIndex += 1
        call_proc(eventhandler,{...})
        returnValue = returnStack[returnStackIndex]
        returnStackIndex -= 1
        returnStack = returnStack[1..length(returnStack)-1]
end procedure

Jeffrey Fielding
JJProg at cyberbury.net
http://members.tripod.com/~JJProg/