#9345: Data.List.inits is extremely slow -------------------------------------+------------------------------------- Reporter: dfeuer | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: | Version: 7.8.3 libraries/base | Keywords: Resolution: | Operating System: Unknown/Multiple Differential Revisions: | Type of failure: Runtime Architecture: | performance bug Unknown/Multiple | Test Case: Difficulty: Easy (less | Blocking: than 1 hour) | Blocked By: | Related Tickets: | -------------------------------------+------------------------------------- Comment (by dfeuer): Replying to [comment:1 nomeata]:
I would find it strange to add such complexity “just for” `inits`. Now, if we had such a `Queue` type (which looks useful in general) in base anyways, using it would be a different story...
If it were added, it wouldn't be called `Queue`, because (unlike the real banker's queue) it's actually incapable of implementing `uncons` efficiently. It's really just a very limited, but very fast and light, list builder. If it's useful for things other than implementing `inits`, I would not be opposed to adding it in a separate module with some sufficiently clear name. I don't know enough about what sorts of things should and should not be provided by base to really comment much beyond that. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9345#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler