import type { AnyCaller } from "../error/BaseError.js";
/** Is a value a boolean? */
export declare function isBoolean(value: unknown): value is boolean;
/** Is a value true? */
export declare function isTrue(value: unknown): value is true;
/** Is a value false? */
export declare function isFalse(value: unknown): value is false;
/** Is a value truthy? */
export declare function isTruthy(value: unknown): boolean;
/** Is a value falsey? */
export declare function isFalsey(value: unknown): boolean;
/** Assert that a value is a boolean. */
export declare function assertBoolean(value: unknown, caller?: AnyCaller): asserts value is boolean;
/** Assert that a value is true. */
export declare function assertTrue(value: unknown, caller?: AnyCaller): asserts value is true;
/** Assert that a value is false. */
export declare function assertFalse(value: unknown, caller?: AnyCaller): asserts value is false;
/** Assert that a value is truthy. */
export declare function assertTruthy(value: unknown, caller?: AnyCaller): asserts value is true;
/** Assert that a value is falsy. */
export declare function assertFalsy(value: unknown, caller?: AnyCaller): asserts value is false;