[Haskell] Read Instances for Data.Map and Data.Set

Remi Turk rturk at science.uva.nl
Mon Oct 24 07:43:15 EDT 2005


On Mon, Oct 24, 2005 at 11:35:04AM +0100, Simon Marlow wrote:
> On 22 October 2005 06:21, Donald Bruce Stewart wrote:
> 
> > The ones I can think of off the top of my head. Of course, these are
> > weird for various reasons though:
> > 
> >     > show $ toDyn (1::Int)     -- Dynamic has no Read
> >     "<<Int>>"
> > 
> >     > show $ typeOf (1::Int)    -- TypeRep as no Read
> >     "Int"
> 
> That reminds me, the Show instance for Exception is similarly bogus.
> 
> Cheers,
> 	Simon

And the one from Text.Show.Functions obviously, and Handle's and
Socket's and ClockTime's and so on...

I think we shouldn't be bothered about ``read . show === id'' not
holding for types where it doesn't even typecheck...

Groeten,
Remi

-- 
Nobody can be exactly like me. Even I have trouble doing it.


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