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

Method in [Declaration](/2.5/api/csharp/yarn.compiler/yarn.compiler.declaration.md)

## Summary

Creates a new instance of the [Declaration](/2.5/api/csharp/yarn.compiler/yarn.compiler.declaration.md) class, using the given name, type and default value.

```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.                                                                                     |
| [Yarn.IType](/2.5/api/csharp/yarn/yarn.itype.md) type | The type of the 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.                                                                              |

## Returns

A new instance of the [Declaration](/2.5/api/csharp/yarn.compiler/yarn.compiler.declaration.md) class.


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