Leif K-Brooks: >http://python.org/doc/current/lib/module-pprint.html#l2h-749
Thank you very much, I see that the function is already there, even with the same name :-) I've seen that it doesn't work for all my tests, like this one with n = 3000: from pprint import isrecursive from time import clock n = 950 print "n =", n l = [] for i in xrange(n): l = [n-i, l] if n < 30: print l t = clock() assert not isrecursive(l) print round(clock()-t, 3), "s" In the function _safe_repr of the pprint.py module there is a recursive call: orepr, oreadable, orecur = _safe_repr(o, context, maxlevels, level) Probably this _safe_repr function can be modified (with a lot of work?) to be iterative (using a list as a stack) to avoid such stack overflows (the list too can overflow, but its capacity is enough for most purposes). Python doesn't have C-like unsafe buffer overrun, so using a list as stack probably improves security a little, and probably makes _safe_repr faster. See you, Bearophile -- http://mail.python.org/mailman/listinfo/python-list
