[Haskell-cafe] poor perfomance of indexU in uvector package

Don Stewart dons at galois.com
Sun Nov 15 12:59:49 EST 2009

> Hello
> This post meant to be literate haskell.
> I found that perfomace of indexU is very poor and it is not fast O(1)
> operation which is very surprising. Here is some benchmarcking I've
> done. Everything compiled with -O2

You're using the streamed version when its not fusing. Use the
non-streaming direct implementation exported from Data.Array.Vector.UArr

This is really an API bug, but I've not had time to sanitize the use.

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