Theoretically, using fractionals as list labels requires unbounded amounts of memory to store the fractions. In practice that is extremely limitted. But the dif

Theoretically, using fractionals as list labels requires unbounded amounts of memory to store the fractions. In practice that is extremely limitted. But the difference becomes really a problem. If you are not just assigning ordered labels to a collection, but if you want to use these labels directly as array indices to store the elements. That would be a more literal modelling of the library sorting problem.