On Dec 15, 3:17 am, leif <not.rea...@online.de> wrote: > +1 > > There's a slight difference between infinite and [non-]enumerable sets > you know... ;-)
Right. ;-) What I would like to prevent is a hang when naively asking for the *entire* list of elements of an infinite set, without having to know (or investigate beforehand) that the set is infinite. I understand the desire and need for iterators for these sets, as Robert described. Despite appearances, I wasn't proposing killing that behavior. A quick experiment would indicate that checking if a set knows it is infinite early in _list_from_iterator_cached will prevent most simple/obvious cases of these hangs without breaking anything else. I'll put up a real patch for consideration soon. > What about requiring a 'count' parameter to .list() if [we know that] > the set is not finite? I'd think that If someone wants a handful of elements from a set they know is infinite, then they should construct the iterator (which the list-building routine is using anyway) and just get their elements from that? A count keyword would be useful, though then the caching behavior of these lists might need to be refined. Rob -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
