import type { TypeGuardFn } from './isType';
/**
 * Creates a type guard function for object schemas with improved nested type support.
 *
 * This function is similar to `isType` but provides better support for deeply nested structures
 * by automatically handling nested type guards without requiring explicit `isType` calls for each level.
 *
 * Key differences from `isType`:
 * - Automatically detects and handles nested object structures
 * - Provides better error messages for nested validation failures
 * - Supports both inline object definitions and existing type guards
 * - Maintains backward compatibility with existing type guard patterns
 *
 * @template T - The type to validate
 * @param schema - Object mapping property keys to their type guard functions or inline object definitions
 * @returns A type guard function that validates the object structure
 *
 * @example
 * ```typescript
 * import { isSchema, isString, isNumber, isBoolean } from 'guardz';
 *
 * // Simple nested structure
 * const isUser = isSchema({
 *   name: isString,
 *   age: isNumber,
 *   address: {
 *     street: isString,
 *     city: isString,
 *     zipCode: isNumber,
 *   },
 *   preferences: {
 *     theme: isString,
 *     notifications: isBoolean,
 *   },
 * });
 *
 * // Complex nested structure with arrays
 * const isComplexUser = isSchema({
 *   id: isNumber,
 *   profile: {
 *     name: isString,
 *     email: isString,
 *     contacts: [{
 *       type: isString,
 *       value: isString,
 *     }],
 *   },
 *   settings: {
 *     theme: isString,
 *     notifications: {
 *       email: isBoolean,
 *       push: isBoolean,
 *     },
 *   },
 * });
 * ```
 */
export declare function isSchema<T>(schema: any): TypeGuardFn<T>;
export declare const isShape: typeof isSchema;
export declare const isNestedType: typeof isSchema;