in src/nms-api/Util/PrimitiveMap.cs [205:214]
public IList GetList(String key)
{
Object value = GetValue(key);
if (value != null && !(value is IList))
{
throw new NMSException("Property: " + key + " is not an IList but is: " + value);
}
return (IList) value;
}