TypeScript adds a typeof operator you can use in a type context to refer to the type of a variable or property : let s = “hello”; let n : typeof s ; let n: string. This isn’t very useful for basic types, but combined with other type operators, you can use typeof to conveniently express many patterns.

TypeScript adds a typeof operator you can use in a type context to refer to the type of a variable or property : let s = “hello”; let n : typeof s ; let n: string. This isn’t very useful for basic types, but combined with other type operators, you can use typeof to conveniently express many patterns.