[Haskell-beginners] How to use Text.Printf w/ custom types

[Baa]

Oh, seems that it's my error! You are right.

> PrintfArg does not have toUPrint. The functions in there are
> formatArg and parseFormat.
> 
> PrintfType is according to its documentation, an interface that you
> shall not implement yourself.
> 
> Baa <aquagnu at gmail.com> schrieb am Fr., 24. Nov. 2017 um 15:08 Uhr:
> 
> > I talked about PrintfType and its method `hspr`.
> >
> > With PrintfArgs the same problem:
> >
> >   instance PrintfArg JobEvent where
> >     toUPrintf _ = UString "aaa"
> >
> >       ^^^ toUPrintf is not visible ERROR here...
> >
> > Header of this file looks like:
> >
> >   module Text.Printf(
> >      printf, hPrintf,
> >      PrintfType, HPrintfType, PrintfArg, IsChar
> >   ) where
> >
> > so methods are not exported? And I don't see any Internal
> > subpackage... OK, no problem, I switched already to very cool
> > `formatting` library :)
> >
> > Thanks a lot!
> >
> >  
> > > It appears PrintfArg and its methods are fully exported.
> > >
> > > On Fri, Nov 24, 2017 at 8:19 AM, Baa <aquagnu at gmail.com> wrote:
> > >  
> > > > But how to do it if "methods" are not exporting?
> > > >  
> > > > > According to
> > > > > https://hackage.haskell.org/package/base-4.10.0.0/docs/  
> > > > Text-Printf.html#g:2,  
> > > > > you only need to implement `PrintfArg`. There is also an
> > > > > example for `()`.
> > > > >
> > > > > Baa <aquagnu at gmail.com> schrieb am Fr., 24. Nov. 2017 um 13:33
> > > > > Uhr:  
> > > > > > Hello All!
> > > > > >
> > > > > > As I understand to use Text.Printf.printf with custom types
> > > > > > or to return result as Text instead of String I must
> > > > > > implement some class instances: PrintfType, PrintfArg. But
> > > > > > how to do this if they are exported from module as
> > > > > > type-names only - without its methods (i.e. not "Printf
> > > > > > (..)", but "Printf") ?
> > > > > >
> > > > > > I tried to import Text.Printf.Internal but seems that no
> > > > > > such submodule...
> > > > > >
> > > > > > Any ideas?
> > > > > >
> > > > > > ===
> > > > > > Best regards, Paul
> > > > > > _______________________________________________
> > > > > > Beginners mailing list
> > > > > > Beginners at haskell.org
> > > > > > http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
> > > > > >  
> > > >
> > > > _______________________________________________
> > > > Beginners mailing list
> > > > Beginners at haskell.org
> > > > http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
> > > >  
> >
> > _______________________________________________
> > Beginners mailing list
> > Beginners at haskell.org
> > http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
> >