Enumerations allow us to define a set of named constants. Since the TypeScript 2.4 release, these named constant values can be string values. Originally, they could only be numeric values:
enum CardinalDirection { Up, Down, Left, Right}
A common workaround to this limitation was the usage of union types of literal types:
type CardinalDirection = "North" | "East" | "South" | "West";function move(distance: number, direction: CardinalDirection) { // ...}move(1,"North"); // Okaymove(1,"Nurth"); // Error!
Since the TypeScript 2.4 release, enumerations with string values are also supported:
enum CardinalDirection { Red = "North", Green = "East", Blue = "South", West = "West"}
