---
jsApi: true
title: "[F] checkDuplicateTypeName"

---
```ts
checkDuplicateTypeName(
  program,
  type,
  name,
  existing): void
```

## Parameters

| Parameter | Type |
| :------ | :------ |
| `program` | `Program` |
| `type` | `Type` |
| `name` | `string` |
| `existing` | `undefined` \| `Record`< `string`, `unknown` \> |

## Returns

`void`
