/// <summary>
/// checks whether the current value of a variable is null (not nullable types return false)
/// </summary>
/// <param name="udonBehaviour"></param>
/// <param name="symbolName"></param>
/// <param name="variableType"></param>
/// <returns></returns>
/// <exception cref="ArgumentException">if udonBehaviour is invalid</exception>
public static bool IsInspectorVariableNull(this UdonBehaviour udonBehaviour,
string symbolName,
out Type variableType)
{
udonBehaviour.GetInspectorVariable(symbolName, out var variableValue, out variableType);
return(variableType.IsNullable() && variableValue.IsUnityObjectNull());
}