Type Alias DigitCharacter

DigitCharacter: "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9"

Matches any digit as a string ('0'-'9').

import type {DigitCharacter} from 'type-fest';

const a: DigitCharacter = '0'; // Valid
// @ts-expect-error
const b: DigitCharacter = 0; // Invalid