[Haskell-cafe] ANNOUNCE: uuid-1.2.6
aslatter at gmail.com
Fri Sep 21 13:38:53 CEST 2012
On Fri, Sep 21, 2012 at 12:30 AM, David Fox <ddssff at gmail.com> wrote:
> I was wondering about this:
> -- My goal with this instance was to make it work just enough to do what
> -- I want when used with the HStringTemplate library.
> instance Data UUID where
> toConstr uu = mkConstr uuidType (show uu)  (error "fixity")
> gunfold _ _ = error "gunfold"
> dataTypeOf _ = uuidType
> Is there any reason not to just say "deriving Data" in the type declaration?
I didn't want my 'Data' instance to leak the details of the
constructor. Also I don't know much about how 'Data' works.
I think a similar conversation is going on about the Data declarations
in the 'containers' library.
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