predictype/dist/cjs/predicates/objects/objectKey.d.ts

PredicType is a library of pre-built and tested predicates for TypeScript, covering various data types and operations.

import { ObjectKeyOper } from '../../enums/objects.js';
/**
 * Checks if an object has or lacks a specific key (string or symbol) using the specified operation.
 *
 * @param source The object to check.
 * @param oper The key operation to perform (e.g. 'has_key', 'lacks_key').
 * @param key The key to check.
 * @returns True if the key check is valid according to the operator, otherwise false.
 *
 * @throws {Error} If the operation is not recognized.
 *
 * @example
 * const obj = { foo: 1 };
 * const obj2 = {};
 * const sym = Symbol('baz');
 * Object.defineProperty(obj2, sym, { value: 2 });
 *
 * objectKey(obj, 'has_key', 'foo'); // true
 * objectKey(obj, 'lacks_key', 'bar'); // true
 * objectKey(obj2, 'has_key', sym); // true
 *
 * @remarks
 * Supported Operators:
 * - **CONTAINS_KEY**: Object has the key
 * - **LACKS_KEY**: Object does not have the key
 */
export declare function objectKey(source: object, oper: ObjectKeyOper, key: string | symbol): boolean;