guardz/dist/typeguards/isObjectWithEachItem.d.ts

A simple and lightweight TypeScript type guard library for runtime type validation.

import type { TypeGuardFn } from './isType';
/**
 * Creates a type guard that checks if a value is a plain object where each property value matches a specific type.
 *
 * This is a higher-order function that takes a type guard for the property values and returns
 * a type guard for objects containing those values. Only checks enumerable own properties.
 *
 * @param predicate - The type guard function to apply to each property value
 * @returns A type guard function that checks if the value is an object with valid property values
 *
 * @example
 * ```typescript
 * import { isObjectWithEachItem, isString, isNumber } from 'guardz';
 *
 * const isStringRecord = isObjectWithEachItem(isString);
 * const isNumberRecord = isObjectWithEachItem(isNumber);
 *
 * console.log(isStringRecord({ a: "hello", b: "world" })); // true
 * console.log(isStringRecord({})); // true (empty object is valid)
 * console.log(isStringRecord({ a: "hello", b: 123 })); // false (mixed types)
 * console.log(isStringRecord([])); // false (array is not a plain object)
 * console.log(isStringRecord(null)); // false
 *
 * // With type narrowing
 * const data: unknown = getUserInput();
 * if (isStringRecord(data)) {
 *   // data is now typed as Record<string, string>
 *   Object.keys(data).forEach(key => {
 *     console.log(data[key].toUpperCase());
 *   });
 * }
 * ```
 */
export declare function isObjectWithEachItem<T>(predicate: TypeGuardFn<T>): TypeGuardFn<Record<string, T>>;