Feldspar.Option

Documentation

data Option a

Constructors

Option

Fields

isSome :: Data Bool

fromSome :: a

Instances

Monad Option

Functor Option

Syntax a => Syntactic (Option a)

(Syntactic (Option a), ~ (* -> *) (Domain (Option a)) FeldDomainAll, Type (Internal (Option a)), Syntax a) => Syntax (Option a)

desugarOption :: Type a => Option (Data a) -> Data (Bool, a)

One-layer desugaring of Option

sugarOption :: Type a => Data (Bool, a) -> Option (Data a)

One-layer sugaring of Option

some :: a -> Option a

none :: Syntax a => Option a

option :: Syntax b => b -> (a -> b) -> Option a -> b

oplus :: Syntax a => Option a -> Option a -> Option a

Conditional choice operator

(?>) :: Data Bool -> a -> Option a

Conditional choice operator. Can be used together with <? to write guarded choices as follows:

 prog :: Data Index -> Data Index
 prog a
     =  a+1 <? a==0
     ?> a+2 <? a==1
     ?> a+3 <? a==2
     ?> a+4 <? a==3
     ?> a+5

(<?) :: Syntax a => a -> Option a -> a