Reason BST Blog Post variants

ReasonBSTVariant.re

/* pet is called a type constructor. Dog, Cat, and
   Hamster are called value constructors or tags*/
type pet =
  | Dog
  | Cat
  | Hamster;

/* myPet is of type pet */
let myPet = Dog;

/* Variants may also hold data */
type pets =
  | Dog(string)
  | Cat(string)
  | Hamster(string);

let myPet = Dog("Buddy");