CODE EXAMPLE FOR TYPESCRIPT

typescrpt create a type

type numberOrString = number | string
type numberType = 1|2|3|4|5|6|7|8
type letterType = 'a'|'b'|'c'|'d'|'e'|'f'|'g'|'h'|'i'
// https://www.typescriptlang.org/docs/handbook/2/types-from-types.html