aaditmshah

Design Patterns in Haskell

Creational Patterns

Factory Method

1. Create a Product type class.
2. Create an existential type SomeProduct for the Product type class.
3. Create a Factory type class with a createProduct method.

aaditmshah

type Assert = (condition: boolean, message: string) => asserts condition;

const assert: Assert = (condition, message) => {
  if (!condition) throw new Error(message);
};

type List<A> = Cons<A> | Empty;

interface Cons<out A> {
  type: 'Cons';