20 Jan
2014
20 Jan
'14
6:48 a.m.
Hi Cafe, I have these typeclasses defined: class UA a where ... class RA a where ... and this data definition data (UA u, RA r) => AD u r = AD { ... } I have another data definition data ACT aur c = ACT { x :: aur, ... } but the type 'aur' should be restricted to (AD u r) only. (I would like to keep 'aur' as 1 parameter, not as data ACT u r c = ACT { x :: AD u r, ... } ) How can such constraint be defined? Best regards, vlatko