guardz
Version:
A simple and lightweight TypeScript type guard library for runtime type validation.
58 lines (57 loc) • 1.92 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.isError = void 0;
const generateTypeGuardError_1 = require("./generateTypeGuardError");
/**
* Checks if a value is an Error object.
*
* This type guard validates that a value is an Error instance or a subclass of Error.
* It's useful for error handling and validation in try-catch blocks.
*
* @param value - The value to check
* @param config - Optional configuration for error handling
* @returns True if the value is an Error object, false otherwise
*
* @example
* ```typescript
* import { isError } from 'guardz';
*
* console.log(isError(new Error('Something went wrong'))); // true
* console.log(isError(new TypeError('Invalid type'))); // true
* console.log(isError(new ReferenceError('Not defined'))); // true
* console.log(isError('error message')); // false (string)
* console.log(isError(123)); // false (number)
* console.log(isError({ message: 'error' })); // false (plain object)
*
* // With type narrowing
* const data: unknown = getErrorData();
* if (isError(data)) {
* // data is now typed as Error
* console.log('Error message:', data.message);
* console.log('Error stack:', data.stack);
* }
*
* // With error handling
* try {
* // Some operation that might throw
* throw new Error('Operation failed');
* } catch (error) {
* if (isError(error, { identifier: 'caughtError' })) {
* // error is now typed as Error
* console.error('Caught error:', error.message);
* } else {
* console.error('Unknown error type:', error);
* }
* }
* ```
*/
const isError = function (value, config) {
if (!(value instanceof Error)) {
if (config) {
config.callbackOnError((0, generateTypeGuardError_1.generateTypeGuardError)(value, config.identifier, 'Error'));
}
return false;
}
return true;
};
exports.isError = isError;