import { ValidationException } from './ValidationException';
/**
 * Is the value a generator function?
 * See: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/GeneratorFunction
 *
 * @example
 * ```ts
 * isGeneratorFunction(function* () { yield 'a' }) // true
 * isGeneratorFunction(() => 'a') // false
 * ```
 *
 * @param value the value to check
 * @returns a boolean indicating whether the value is the expected type
 */
export declare const isGeneratorFunction: (value: unknown) => value is Function;
/**
 * Validate that the value is a generator function.
 * See: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/GeneratorFunction
 *
 * @example
 * ```ts
 * validateGeneratorFunction(function* () { yield 'a' }) // null
 * validateGeneratorFunction(() => 'a') // ValidationException
 * ```
 *
 * @param value the value to check
 * @returns `null` if the value is the expected type or a `ValidationException`
 * if not
 */
export declare const validateGeneratorFunction: (value: unknown) => ValidationException | null;
/**
 * Assert that the value is a generator function.
 * See: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/GeneratorFunction
 *
 * @example
 * ```ts
 * assertGeneratorFunction(function* () { yield 'a' }) // void
 * assertGeneratorFunction(() => 'a') // throws AssertionException
 * ```
 *
 * @param value the value to check
 * @throws an `AssertionException` if the value is not the expected type
 */
export declare const assertGeneratorFunction: (value: unknown) => asserts value is Function;