On 2014-10-26, Tim Delaney <timothy.c.dela...@gmail.com> wrote: > On 27 October 2014 01:14, Jon Ribbens <jon+use...@unequivocal.co.uk> wrote: >> I have a need, in a Python C extension I am writing, for lists and >> dictionaries with "lazy evaluation" - by which I mean that at least >> some of the values in the lists/dictionaries are "proxy objects" >> which, rather than returning as themselves, should return the thing >> they are a proxy for when retrieved. This is because retrieving >> the proxied objects is expensive and only a small minority of them >> will actually be accessed, so retrieving them all before they are >> actually accessed is massively inefficient. > > Why not put proxy objects into the list/dict?
That's precisely what I am doing. The point is that when they are retrieved they need to be resolved into the genuine objects. > Have a look at the weakref module for an API that may be suitable > for such proxy objects (if you used the same API, that would also > allow you to transparently use weakrefs in your lists/dicts). Hmm, the idea behind that appears to be to create a proxy that emulates every possible method of every conceivable type. My method of only emulating the list and dict methods seems to be somewhat simpler for my purpose ;-) -- https://mail.python.org/mailman/listinfo/python-list
