Skip has a concept of a "intern heap" that contains all the values that are going to be used for memoization. By default everything is allocated on the stack/he

Skip has a concept of a "intern heap" that contains all the values that are going to be used for memoization. By default everything is allocated on the stack/heap. When you want to memoize a function, then we move all the arguments to the intern heap which makes structurally equal values have the same pointer. Then we can figure out quickly if two immutable values are equal. We have an intern() function that lets you move a value to the intern heap manually. We are also thinking about adding a field for objects such that once it is interned somewhere, if you intern it again, it's a no-op and we use the pointer in the object. This would avoid accidentally increasing the complexity of an algorithm by repeatedly interning the same value.