/**
 * A unary function that returns true or false for a given `value`.
 *
 * @since v0.1.2
 */
export type Predicate<T> = (value: T) => boolean;
/**
 * A type predicate. Returns `true` if a given `value` is `boolean`.
 *
 * @since v0.10.0
 */
export declare function isBoolean(value: unknown): value is boolean;
/**
 * A type predicate. Returns `true` if a given `value` is not `boolean`.
 *
 * @since v0.10.0
 */
export declare function isNotBoolean<T>(value: T | boolean): value is T;
/**
 * Returns true when the value is neither undefined, null, false, NaN, 0, -0, 0n (a `BigInt` zero),
 * "" (an empty string), or the `document.all` builtin.
 *
 * @see https://developer.mozilla.org/en-US/docs/Glossary/Truthy
 *
 * @since v0.3.0
 */
export declare function isTruthy(value: unknown): boolean;
/**
 * Returns true when the value is undefined, null, false, NaN, 0, -0, 0n (a `BigInt` zero), "" (an empty string),
 * or the `document.all` builtin.
 *
 * @see https://developer.mozilla.org/en-US/docs/Glossary/Falsy
 *
 * @since v0.3.0
 */
export declare function isFalsy(value: unknown): boolean;
/**
 * Creates a {@linkcode Predicate} that is true if its argument strictly equals a given `input`.
 *
 * @since v0.2.0
 */
export declare function is<T>(input: T): Predicate<T>;
/**
 * Creates a {@linkcode Predicate} that is true if its argument does not equal a given `input`.
 *
 * @since v0.2.0
 */
export declare function isNot<T>(input: T): Predicate<T>;
/**
 * Creates a {@linkcode Predicate} that inverses the result of a given {@linkcode Predicate}.
 *
 * @since v0.2.0
 */
export declare function not<T>(predicate: Predicate<T>): Predicate<T>;
/**
 * Creates a {@linkcode Predicate} that is true when all given `predicates` are true.
 *
 * This is a logical `AND` operation.
 *
 * @since v0.2.0
 */
export declare function all<T>(...predicates: Predicate<T>[]): Predicate<T>;
/**
 * Creates a {@linkcode Predicate} that is true when at least one of given `predicates` is true.
 *
 * This is a logical `OR` operation.
 *
 * @since v0.2.0
 */
export declare function either<T>(...predicates: Predicate<T>[]): Predicate<T>;
/**
 * Creates a {@linkcode Predicate} that is true when none of given `predicates` is true.
 *
 * @since v0.2.0
 */
export declare function neither<T>(...predicates: Predicate<T>[]): Predicate<T>;
/**
 * Creates a {@linkcode Predicate} that is true
 * when at least a given `minimum` number of given `predicates` is true.
 *
 * @since v0.2.0
 */
export declare function atLeast<T>(minimum: number, ...predicates: Predicate<T>[]): Predicate<T>;
/**
 * Creates a {@linkcode Predicate} that is true
 * when no more than a given `maximum` number of given `predicates` is true.
 *
 * @since v0.2.0
 */
export declare function atMost<T>(maximum: number, ...predicates: Predicate<T>[]): Predicate<T>;
/**
 * Creates a {@linkcode Predicate} that is true
 * when exactly a given `count` of given `predicates` is true.
 *
 * @since v0.2.0
 */
export declare function exactly<T>(count: number, ...predicates: Predicate<T>[]): Predicate<T>;