guardz/dist/typeguards/isNil.js

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

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.isNil = void 0;
const generateTypeGuardError_1 = require("./generateTypeGuardError");
/**
 * Checks if a value is null or undefined (nil).
 *
 * @param value - The value to check
 * @param config - Optional configuration for error handling
 * @returns True if the value is null or undefined, false otherwise
 *
 * @example
 * ```typescript
 * import { isNil } from 'guardz';
 *
 * console.log(isNil(null)); // true
 * console.log(isNil(undefined)); // true
 * console.log(isNil("")); // false
 * console.log(isNil(0)); // false
 * console.log(isNil(false)); // false
 * console.log(isNil({})); // false
 *
 * // Useful for checking if a value needs initialization
 * const data: unknown = getUserInput();
 * if (isNil(data)) {
 *   // data is now typed as null | undefined
 *   console.log("Value is null or undefined");
 * }
 * ```
 */
const isNil = function (value, config) {
    if (value !== null && value !== undefined) {
        if (config) {
            config.callbackOnError((0, generateTypeGuardError_1.generateTypeGuardError)(value, config.identifier, 'null | undefined'));
        }
        return false;
    }
    return true;
};
exports.isNil = isNil;