[Haskell] [Haskell-cafe] ANNOUNCE: system-filepath 0.4.5 and system-fileio 0.3.4

Simon Marlow marlowsd at gmail.com
Tue Feb 7 13:24:55 CET 2012

On 06/02/2012 20:32, Ian Lynagh wrote:
> On Sun, Feb 05, 2012 at 07:17:32PM -0800, John Millikin wrote:
>> That was my understanding also, then QuickCheck found a
>> counter-example. It turns out that there are cases where a valid path
>> cannot be roundtripped in the GHC 7.2 encoding.
> This is fixed in GHC 7.4.1.

I think we forgot to mention it in the release notes.  Rountripping of 
FilePath is now fully supported.  The commit in question is this:

commit 7e59b6d50ec4a4400e8730bfd8cfc471c1873702
Author: Max Bolingbroke <batterseapower at hotmail.com>
Date:   Fri Nov 18 17:45:34 2011 +0000

     Go back to using private-use characters in roundtripping

Which was the result of a long discussion on the glasgow-haskell-users 
mailing list:


Separately the unix package added support for undecoded FilePaths 
(RawFilePath), but unfortunately at the same time we started using a new 
extension in GHC 7.4.1 (CApiFFI), which we decided not to document 
because it was still experimental:


In retrospect we should have documented this.  It's not like we don't 
normally dump a load of experimental features on our users and then 
change them later :-)


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