IMHO we shouldn't slow down cached_method just to allow you to write incorrect code (and caching a returned list is a bug). If anything, cached_method should print a warning if the result is mutable so people can fix their code.
On Friday, June 3, 2016 at 1:10:25 PM UTC-4, Simon King wrote: > > Hi All, > > I know it would considerably slow down @cached_method, but what about the > following: > - When a new item for the cache is first computed, test whether it is > hashable. > - Along with the item, store whether it is hashable or not (so that > there's no need to test hashability again). > - If an item is taken from cache, the return either the item itself or a > (deep?) copy of it, depending on whether it is hashable or not. > > In addition to a slow-down, it might break pickles (because it would > change the internal format of the cache). > > So, maybe this is better: Add an option to @cached_method, such as > @cached_method(copy=True) > def list(self) > return list(self) > It means that the resulting wrapper of the list() method will use a > cache, but will always copy the result before returning it. > > Cheers, > Simon > > -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at https://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
