Global variables?

Patrik Jansson
Sun, 2 Feb 2003 18:11:53 +0100 (MET)

On Fri, 31 Jan 2003, Jon Cast wrote:
> Otherwise, though, see my other post on this subject: unsafePerformIO
> will perform its action when the variable is accessed, so you can't
> write a Haskell program which differentiates between what any compiler
> actually does and running the variable allocations before main.

If you initialize this "global variable" with a value from a file which is
changed by main (or over time) then order does matter.

I claim unsafePerformIO is very often unsafe - the question is more like
if the "level of unsafety" is acceptable for a particular application.