System.IO.latin1 docs

[Wolfgang Jeltsch]

Am Donnerstag, den 23.12.2010, 10:09 +0000 schrieb Simon Marlow:
> On 16/12/10 20:53, Wolfgang Jeltsch wrote:
> > Hello,
> >
> > on
> >
> > <http://www.haskell.org/ghc/docs/6.12.2/html/libraries/base-4.2.0.1/System-IO.html#v%3Alatin1>
> >
> > it says:
> >
> >> An attempt to write a character greater than '\255' to a Handle using
> >> the latin1 encoding will result in an error.
> >
> > However, according to my experience (with GHC 6.12.1 and base 4.2.0.0),
> > latin1 just outputs a character '\cccc' as cccc `mod` 256.
> 
> It seems to be working as advertised for me:
> 
> $ ghc-6.12.1 --interactive
> GHCi, version 6.12.1: http://www.haskell.org/ghc/  :? for help
> Loading package ghc-prim ... linking ... done.
> Loading package integer-gmp ... linking ... done.
> Loading package base ... linking ... done.
> Loading package ffi-1.0 ... linking ... done.
> Prelude> import System.IO
> Prelude System.IO>  hSetEncoding stdout latin1
> Prelude System.IO>  putChar '\256'
> *** Exception: <stdout>: hPutChar: invalid argument
>               (character is out of range for this encoding)
> Prelude System.IO>
> 
> I get the same results with 7.0.1.  Can you tell me how to reproduce the 
> problem you're seeing?

I used

    hSetBinaryMode stdout True

instead of

    hSetEncoding stdout latin1    .

The documentation of hSetBinaryMode says:

    This has the same effect as calling hSetEncoding with latin1,
    together with hSetNewlineMode with noNewlineTranslation.

It seems that this sentence is wrong.

Best wishes,
Wolfgang