Re: [Haskell-cafe] Stream fusion and span/break/group/init/tails

So, if I understand correctly, you're using the "online/offline" criterion to resolve non-directed cycles in pipelines? (I couldn't tell how the Shivers paper was related.) Cheers, Edward Excerpts from Ben Lippmeier's message of Sun Apr 21 19:29:29 -0700 2013:

On 22/04/2013, at 12:23 , "Edward Z. Yang" wrote:

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I've got a solution for this problem and it will form the basis of Repa 4, which I'm hoping to finish a paper about for the upcoming Haskell Symposium.

Sounds great! You should forward me a preprint when you have something in presentable shape. I suppose before then, I should look at repa-head/repa-stream to figure out what the details are?

The basic approach is already described in:

Automatic Transformation of Series Expressions into Loops Richard Waters, TOPLAS 1991

The Anatomy of a Loop Olin Shivers, ICFP 2005

The contribution of the HS paper is planning to be: 1) How to extend the approach to the combinators we need for DPH 2) How to package it nicely into a Haskell library.

I'm still working on the above...

Ben.