Thank you for pointing me to Sub::Call::Recur, very interesting!

especially:

It can be thought of as the redo operator, but for subroutines instead of loops.

:)

Actually I once read about recur in a Clojure book and wondered about the advantages to goto &sub

Clearly - and as you demonstrated - there are two:

1. One can use the "usual" call interface f(PARAS) instead of the cumbersome  @_=(PARAS);goto &f

2. Memoize can't intercept and cache calls when goto-like constructions are used.

OTOH Sub::Call::Recur relies on XS code... so I think I'd rather prefer to chose between the need of memoization for repeated runs or for speed and stack-sanity of one time runs.

I think if I need both I could still realize my own memoization hash.