What are the differences between enum and const assertions in TypeScript?

What are the differences between enum and const assertions in TypeScript?

In TypeScript, enums are a way to define a set of named constants, while const assertions allow you to create a constant value that retains its literal type. Enums can be numeric or string-based, whereas const assertions are typically used with objects or arrays.

Can you give me an example of each?

Sure! For an enum, you might have: enum Color { Red, Green, Blue }. For a const assertion, you could use: const colors = ['red', 'green', 'blue'] as const; This makes colors a readonly tuple.

When should I use one over the other?

Use enums when you need a set of related constants that can be referenced by name, especially for numeric values. Use const assertions when you want to create immutable data structures with specific types.

Are there any performance differences?

Generally, enums can have a slight overhead due to their generated code, while const assertions are more lightweight. However, the performance difference is usually negligible in most applications.