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isError - node__util.d.ts - Node documentation
function isError

Usage in Deno

```typescript import { isError } from "node:node__util.d.ts"; ```
isError(object: unknown): object is Error
Deprecated
Since v4.0.0 - Use [types.isNativeError](../.././node__util.d.ts/~/types.isNativeError) instead.
Returns `true` if the given `object` is an `Error`. Otherwise, returns `false`. ```js import util from 'node:util'; util.isError(new Error()); // Returns: true util.isError(new TypeError()); // Returns: true util.isError({ name: 'Error', message: 'an error occurred' }); // Returns: false ``` This method relies on `Object.prototype.toString()` behavior. It is possible to obtain an incorrect result when the `object` argument manipulates `@@toStringTag`. ```js import util from 'node:util'; const obj = { name: 'Error', message: 'an error occurred' }; util.isError(obj); // Returns: false obj[Symbol.toStringTag] = 'Error'; util.isError(obj); // Returns: true ```

Parameters

object: unknown

Return Type

object is Error