What is the TypeScript equivalent of "PropTypes.oneOf" (restrict a variable to subset of values)

Question

In React I can restrict a variable to subset of values, like

PropTypes.oneOf(['Home', 'About']), 

How do I do that in TypeScript?

PS: I am not using TypeScript with React.

Answer 1

You can combine static strings (or any regular type) by defining a union type:

type SomeType = 'Home' | 'About'; 

Or within an interface:

interface SomeType {   prop : 'Home' | 'About'; } 

And of course you can combine other types as well:

type SomeType = string | boolean;