## validationError() function

**Signature:**

```typescript
export declare function validationError(details: string, expressions?: string[], code?: IssueType, diagnostics?: string): OperationOutcome;
```

## Parameters

| Parameter    | Type                        | Description | 
| ------------ | --------------------------- | ----------- | 
| details      | string                      |             | 
| expressions  | string[] _(Optional)_       |             | 
| code         | [IssueType](/content/docs/sdk/core.issuetype) _(Optional)_ |             | 
| diagnostics   | string _(Optional)_          |             |

**Returns:**

OperationOutcome

- [validationError() function](/content/docs/sdk/core.validationerror#validationerror-function/index.html)
- [Parameters](/content/docs/sdk/core.validationerror#parameters/index.html)