type-samurai/src/mod.d.ts

Advanced utility types for Typescript

import { Div } from "./div";
import { Mult } from "./mult";
import { Sub } from "./sub";

/**
 * Returns the remainder of the division of two numbers.
 * @example
 * ```ts
 * // 1
 * type T0 = Mod<1, 2>;
 * // 1
 * type T1 = Mod<1, 3>;
 * ```
 */
export type Mod<Dividend extends number, Divisor extends number> = Div<
  Dividend,
  Divisor
> extends infer Quotient extends number
  ? Mult<Quotient, Divisor> extends infer Product extends number
    ? Sub<Dividend, Product>
    : never
  : never;