For most functors, that is equivalent to point x = undefined
But by that logic, everything is a member of every typeclass... -- Robin On Fri, 13 Mar 2009 17:35:31 +0300 Eugene Kirpichov <[email protected]> wrote: > 'An arbitrary element' means 'undefined will suffice' > > point x = fmap (const x) undefined > > > 2009/3/13 Ross Paterson <[email protected]>: > > On Fri, Mar 13, 2009 at 03:18:15PM +0100, Martijn van Steenbergen > > wrote: > >> Are there any functors f for which no point/pure/return :: a -> f > >> a exists? > > > > No. Choose an arbitrary element shape :: f () and define > > > > point x = fmap (const x) shape > > _______________________________________________ > > Haskell-Cafe mailing list > > [email protected] > > http://www.haskell.org/mailman/listinfo/haskell-cafe > > > > > _______________________________________________ Haskell-Cafe mailing list [email protected] http://www.haskell.org/mailman/listinfo/haskell-cafe
