# additionalDefines

> Additional #define directives passed to compilation of the assembly.

## Definition

* **Type:** Property
* **Namespace:** [UnityEditor.Compilation](/engine/6000.6/script-reference/unityeditor/compilation.md)
* **Assembly:** UnityEditor.CoreModule

> **Warning:**
>
> **Deprecated.** This feature is being deprecated and will be removed in the future. Similar functionality can be achieved using the Roslyn compiler

```csharp
public string[] additionalDefines { get; set; }
```

### Remarks

By default the same #define directives that are added to scripts inside the Assets folder are added the assembly build. This property allows to add additional #define directives.

The default #define directives are in part controlled by [AssemblyBuilder.flags](/engine/6000.6/script-reference/unityeditor/compilation/assemblybuilder/flags.md), [AssemblyBuilder.buildTarget](/engine/6000.6/script-reference/unityeditor/compilation/assemblybuilder/buildtarget.md) and [AssemblyBuilder.buildTargetGroup](/engine/6000.6/script-reference/unityeditor/compilation/assemblybuilder/buildtargetgroup.md).

Additional Resources: [AssemblyBuilder.defaultDefines](/engine/6000.6/script-reference/unityeditor/compilation/assemblybuilder/defaultdefines.md).