as const

as const is a type assertion in TypeScript that allows you to assert that an expression has a specific type, and that its value should be treated as a read-only value.

For example:

const colors = ['red', 'green', 'blue'] as const;

// colors is now of type readonly ['red', 'green', 'blue']

Using as const allows TypeScript to infer more accurate types for constants, which can lead to improved type checking and better type inference in your code.