How to declare a new type from the trade unions?

Question

Suppose I find that I am declaring many things as Foo|Bar|Baz , and I get tired of writing this. How can I declare type Foob = Foo|Bar|Baz so that I can use Foob ?

Answer 1

Just the way you typed.

 type Foo = {}; type Bar = {}; type Ba = {}; declare type Foob = Foo|Bar|Ba; let x:Foob;