[Haskell-cafe] There is something wrong with hprotoc-0.3.1 package.

[Derek Elkins]

On Tue, 2008-10-14 at 07:13 -0500, Antoine Latter wrote:
> On Tue, Oct 14, 2008 at 12:03 AM, Magicloud
> <magicloud.magiclouds at gmail.com> wrote:
> > Hi,
> >   I wanted to install this package. Well,
> > Building hprotoc-0.3.1...
> > ...
> > [3 of 7] Compiling Text.ProtocolBuffers.ProtoCompile.Parser ...
> >
> > Text/ProtocolBuffers/ProtoCompile/Parser.hs:48:0:
> >   Type synonym `GenParser' should have 2 arguments, but has been given 1
> >   In the type synonym declaration for `P'
> >
> >   And it just stopped here.
> 
> This is an incompatibility between parsec-2 and parsec-3.  In
> parsec-2, 'GenParser' is declared with a 'data' declaration, whereas
> in parsec-3 it's a type synonym.  Since type-synonym declared
> type-constructors cannot be partially applied this doesn't work.
> 
> Currently in parsec-3 'GenParser' is declared as:
> 
> > type GenParser tk st = Parsec [tk] st
> 
> We should be able to change it to:
> 
> > type GenParser tk = Parsec [tk]
> 
> in Text.Parsec.String, unless I'm forgetting something else tricky
> about type synonyms.
> 
> Derek, does this sound reasonable?

The problem is Parsec itself is a type synonym.
type Parsec s u = ParsecT s u Identity
so that latter definition of GenParser leads to a partial application of
Parsec.