👉 Ungetatable is a term used in the field of computer science to describe an object or data structure that cannot be converted into a string representation. This means that when you try to convert it into a string, you will receive garbage values or undefined behavior. For example, consider a linked list where each node contains a value and a pointer to the next node. To make this list ungetatable, we need to ensure that there is always at least one "next" node pointing to the previous
