rambda/_ts-toolbelt/src/Function/Return.ts

Lightweight faster alternative to Ramda

import {Function} from './Function'

/** Extract the return type of a **`Function`**
 * @param F to extract from
 * @returns **`any`**
 * @example
 * ```ts
 * import {F} from 'ts-toolbelt'
 *
 * const fn = () => true
 *
 * type test0 = F.ReturnOf<typeof fn>  // boolean
 *
 * type test1 = F.ReturnOf<() => true> // true
 * ```
 */
export type Return<F extends Function> =
    F extends ((...args: any[]) => infer R)
    ? R
    : never