Haskell lets you infinitely recurse while still completing in finite time, and there’s even a function (fix) for that. Doing e.g. fix (+ 2) would be an infinite loop if evaluated, yes, but fix (2 :) would give you a useful value that’s an infinite stream of 2s. (it’s also useful for other things too)
If your specific use case really needs random access to a list while lazy computing the elements just wrap them in
Lazyand put them in a vector.The return type of an infinitely recursive function / infinite loops is ⊥, a type that by definition has no values. (Known in rust as
!)Haskell lets you infinitely recurse while still completing in finite time, and there’s even a function (
fix) for that. Doing e.g.fix (+ 2)would be an infinite loop if evaluated, yes, butfix (2 :)would give you a useful value that’s an infinite stream of 2s. (it’s also useful for other things too)