lem

Lem is a tool for lightweight executable mathematics
val last : 'a list -> 'a
val init : 'a list -> 'a list
val foldl1 : ( 'a -> 'a -> 'a ) -> 'a list -> 'a
val foldr1 : ( 'a -> 'a -> 'a ) -> 'a list -> 'a
val findNonPure : ( 'a -> bool ) -> 'a list -> 'a
val unfoldr : ( 'a -> ('b * 'a) option ) -> 'a -> 'b list