[Haskell-beginners] print all days of calendar

[Daniel Fischer]

Am Montag 21 Dezember 2009 17:04:56 schrieb kane96 at gmx.de:
> -------- Original-Nachricht --------
>
> > Datum: Mon, 21 Dec 2009 11:53:02 +0100
> > Von: Daniel Fischer <daniel.is.fischer at web.de>
> > An: beginners at haskell.org
> > CC: kane96 at gmx.de
> > Betreff: Re: [Haskell-beginners] print all days of calendar
> >
> > Am Montag 21 Dezember 2009 11:38:14 schrieb kane96 at gmx.de:
> > > Which function can I use to trim the calendar of a month from the
> >
> > calendar
> >
> > > of the whole year, because I have to implement a function: getMonth ::
> > > Month -> Calendar -> Calendar
> >
> > look at filter or span and break, takeWhile/dropWhile
>
> Dont't find any good examples of this functions that can help me. I think
> it have to be somethink like that, but don't find a way that works:
> getMonth :: Month -> Calendar -> Calendar
> getMonth month year = filter ([1..31],month,year) (calendar year)

Prelude> :t filter
filter :: (a -> Bool) -> [a] -> [a]

So we need a predicate on the type of list elements.

getMonth month cal = filter predicate cal
      where
        predicate (d,m,y) = ??