# CreateVariable(string,Yarn.IType,IConvertible,string)

Method in [Declaration](https://docs.yarnspinner.dev/2.1/api/csharp/yarn.compiler/yarn.compiler.declaration)

## Summary

Creates a new instance of the [Declaration](https://docs.yarnspinner.dev/2.1/api/csharp/yarn.compiler/yarn.compiler.declaration) class, using the given `name` and default value. The `ReturnType` of the new instance will be configured based on the type of `defaultValue` , and the `DeclarationType` will be `Type.Variable` . All other properties will be their default values.

```csharp
public static Declaration CreateVariable(string name, Yarn.IType type, IConvertible defaultValue, string description = null)
```

## Parameters

| Name                                                                           | Description                                                                                                          |
| ------------------------------------------------------------------------------ | -------------------------------------------------------------------------------------------------------------------- |
| `string` name                                                                  | The name of the new declaration.                                                                                     |
| `System.IConvertible` defaultValue                                             | The default value of the declaration. This must be a string, a number (integer or floating-point), or boolean value. |
| `string` description                                                           | The description of the new declaration.                                                                              |
| [Yarn.IType](https://docs.yarnspinner.dev/2.1/api/csharp/yarn/yarn.itype) type |                                                                                                                      |

## Returns

A new instance of the [Declaration](https://docs.yarnspinner.dev/2.1/api/csharp/yarn.compiler/yarn.compiler.declaration) class.