On Fri, Jun 21, 2019 at 01:02:26PM +0000, PICCA Frederic-Emmanuel wrote: > Re-Hello, > > is there a way to apply a function to all constructors of this this type ? > > Instead of doing this ? > > do sg P1 > sg P2 > sg P21 > [...] Use the same `Enum` trick Tobias Brandt described. λ> :t sequence_ $ map print [FirstConstructor ..]