LiamGoodacre

-- We define uncurried versions of Pair and Either to help with type-checking
data Tuple : (Type, Type) -> Type where 
  MkTuple : a -> b -> Tuple (a, b)

data Sum : (Type, Type) -> Type where 
  Left : a -> Sum (a, b)
  Right : b -> Sum (a, b)

-- These are bifunctor versions of projections/injections
data Fst : (Type, Type) -> Type where 

LiamGoodacre

const absurd = (v: never): never => v
const typed = <T,>(v: T): T => v
type Kinded<A extends B, B> = A
type Norm<T> = T extends T ? { [k in keyof T]: T[k] } : never

//

interface Condition { present: unknown; absent: unknown }
type Cond<P, A> = Condition & { present: P, absent: A }
type Not<C extends Condition> = Cond<C['absent'], C['present']>