typescript-flow-haskell-types-comparison

Type	Haskell	TypeScript	Flow	JsDoc	JSON Schema
Union	data Shape = Circle | Triangle	type Shape = CircleInterface | TriangleInterface	var Shape: CircleVar | TriangleVar	`({x: number, y: number, r: number}	{{x: number, y: number, a: number, b: number, c: number}})`
Product	Data Circle = Int Int Int	interface Circle {x: number; y: number; radius: number }	var Circle = {x: number, y: number, radius: number}	{{x: number; y: number; radius: number}}	type: "object", properties: {x: "number", y: "number", radius: "number"}
Nullable	Maybe type	type T1 = (x?: number)	var Salary = ?number	{?number}	Depends on parser, either type: null if it supports undefined as well or using required
Non-nulalble	-	let s = e!.name	?	{!{number}}	-
Discriminated union	Pattern matching in type constructor	Understanding context	Understanding context	-	-
Generics	data Maybe a = Nothing | Just a	interface GenericObject<T> {foo: T;}	type GenericObject<T> = { foo: T };	-	-