31 Jan
2003
31 Jan
'03
7:47 a.m.
Pavel G. Zhbanov wrote:
Is it even possible to make a "global variable" in Haskell? If yes, how?
The usual fudge is: import IORef import IOExts globalVar :: IORef Int globalVar = unsafePerformIO $ newIORef 0 However, beware of creating more than one "global variable" of the same type. If you enable optimisation, common subexpression elimination may result in both names referring to the same IORef. -- Glynn Clements <glynn.clements@virgin.net>