chad.scherrer:
they currently use two different fusion systems. bytestring uses an older version of what is now stream fusion. at some point we'll switch bytestrings over to using the new stuff in the stream-fusion package, since its a lot better.
Oh, that's pretty interesting. I had assumed bytestring had the latest fusion stuff.
ah, you assume stream-fusion lists are slower. for list stuff, since 6.8, i've only seen things the same speed or better. but if you have a program doing the wrong thing, it would be worth looking at.
I was just going by the "Lists to Streams to Nothing At All" paper. That's great that it's gotten faster! Does that mean the path for replacing Data.List with this is any clearer?
Not yet. We still don't have a good system for fusing nested concatMaps, that GHC likes, which come up when you desugar list comprehensions. If you can live without too many comprehensions, then the stream-fusion package is entirely viable. -- Don