export declare const isDefined: <T = unknown>(o?: T) => o is NonNullable<T>;
export declare const isUndefined: (v?: unknown) => v is never;
export declare const isEmpty: (o?: unknown) => boolean;
export declare const isNotEmpty: <T = unknown>(o?: unknown) => o is NonNullable<T>;
export declare const isString: (o?: unknown) => o is string;
export declare const isIsoDateString: (o?: unknown) => o is string;
export declare const isBoolean: (o?: unknown) => o is boolean;
export declare const isTrue: (o?: unknown) => o is true;
export declare const isNumber: (o?: unknown) => o is number;
export declare const isObject: (o?: unknown) => o is Record<string, unknown>;
export declare const isEmptyObject: (o?: unknown) => boolean;
export declare const isFunction: (o?: unknown) => o is (...params: unknown[]) => unknown;
export declare const isArray: <T = any>(o?: unknown) => o is Array<T>;
export declare const isIn: (o: unknown, values: unknown[]) => boolean;
export declare const isIntersecting: (o?: unknown[], values?: unknown[]) => boolean;
export declare const isError: (e: unknown) => e is Error;
export declare const isNotPresent: (...os: unknown[]) => boolean;
export declare const isPresent: (...os: unknown[]) => boolean;