, (Opt_LiberalTypeSynonyms, turnOn, Opt_ExplicitForAll)
, (Opt_ExistentialQuantification, turnOn, Opt_ExplicitForAll)
, (Opt_PolymorphicComponents, turnOn, Opt_ExplicitForAll)
+ , (Opt_FlexibleInstances, turnOn, Opt_TypeSynonymInstances)
, (Opt_RebindableSyntax, turnOff, Opt_ImplicitPrelude) -- NB: turn off!