Well first of all, both are abstract concepts. No they aren't. A stack is a specific type of data structure. Recursion isn't even specific to computers. in co

Well first of all, both are abstract concepts. No they aren't. A stack is a specific type of data structure. Recursion isn't even specific to computers. in computer science stacks are considered to be an abstract data type I think you meant data structure and they aren't both concepts. Of course, another way to refer to this kind of a structurally induced data type is to call it recursive. You are making a linked list. A node in a traditional linked list has data and a pointer to the next node. This is what you are making here. Just because you over complicate a stack by using a linked list, it doesn't mean a 'stack' and 'recursion' are the same thing. Fundamentally this is functional programming silver bullet syndrome. These things really have nothing to do with recursion, haskell is just putting a square peg in a round hole by using recursion for iteration and linked lists. It's all fun and games until you get past trivial examples. Then pretending complex iteration and data structures are best done with recursion aren't so fun anymore and you want to control what is actually happening. One example is this rust quicksort being 40x faster than haskell https://github.com/LightAndLight/how-fast-does-it-quicksort https://github.com/LightAndLight/how-fast-does-it-quicksort