[Haskell-cafe] How efficient is read?

[Gwern Branwen]

On Tue, May 11, 2010 at 12:16 AM, Tom Hawkins <tomahawkins at gmail.com> wrote:
>>
>> The tarball was missing its Rules.hs; as it happens, GHC has a module
>> named Rules.hs as well, hence the confusing error. I've uploaded a
>> fresh one that should work.
>
> Thanks.  This builds and installs fine.
>
> But I think there is something wrong with the generated parser.  It
> doesn't look for (..) groupings.  For example:
>
> data Something = Something Int (Maybe String)
>  deriving Show {-! derive : Parse !-}
>
> There is nothing in the generated parser to look for parens around the
> Maybe in case it is a (Just string).
>
> Am I missing something?

I don't know. If you could check whether the original Drift has that
error as well, then I suspect Drift's author, Meachem, would be
interested to know. (I only maintain drift-cabalized as a packaging
fork; I tried not to change any actual functionality.)

-- 
gwern