Jonathan Cast wrote:
On Thu, 2008-08-28 at 10:00 +0100, Adrian Hey wrote:
Lennart Augustsson wrote:
I don't don't think global variables should be banned, I just think they should be severly discouraged.
If you're saying a language should not provide a sound way to do this (as I believe you are), then AFAICT for all practical purposes you *are* saying you think global variables should be banned.
Where are we going to be if the unsafePerformIO hack ever becomes *really* unsafe?
and..
I'm certain you can write a kernel in Haskell where the only use of global variables is those that hardware interfacing forces you to use. But what you haven't explained is why this is even desirable? I don't doubt it's true in an academic sense if you don't mind sacrificing safety
What `safety' is being sacrificed?
and modularity.
What modularity?
As I've pointed out several times already you can find simple examples in the standard haskell libs. So far nobody has accepted my challenge to re-implement any of these "competantly" (I.E. avoiding the use of global variables). Why don't you try it with Data.Unique and find out :-) Regards -- Adrian Hey