IO Bool -> Bool
Brandon Michael Moore
Thu, 14 Aug 2003 11:30:11 -0700 (PDT)
On Thu, 14 Aug 2003, Wolfgang Jeltsch wrote:
> On Thursday, 2003-08-14, 17:05, CEST, Kevin S. Millikin wrote:
> > On Wednesday, August 13, 2003 11:20 PM, Tn X-10n
> > [SMTP:firstname.lastname@example.org] wrote:
> > > is it possible to convert IO Bool to Bool?
> > Sure. Which Bool do you want? True?
> > > toTrue :: IO Bool -> Bool
> > > toTrue x = True
> > Or False?
> > > toFalse :: IO Bool -> Bool
> > > toFalse x = False
boolFromIO :: IO Bool -> Bool
boolFromIO = boolFromIO
if you want to be even less useful :)
> I wouldn't call these *conversion* functions because they don't look at their
> > Maybe that's not what you had in mind.
> Surely not.
I'm surprise nobody has mentioned unsafePerformIO (:: IO a -> a).
As the name suggests, it isn't referentially transparent.
Are you sure you need a function of type IO Bool -> Bool? What are you
trying to do?