Add Lift instances #332
Add Lift instances #332
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Data/Primitive/Array.hs
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| -- of the list does not match the given length, this makes demons fly | ||
| -- out of your nose. We use it in the 'Lift' instance. If you edit the | ||
| -- splice and break it, you get to keep both pieces. | ||
| unsafeArrayFromListN' :: Int -> [a] -> Array a |
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What would happen if we wrote this as a fold? Would GHC be able to make good decisions about when to build it as a list and convert it to an array vs. building it directly as an array (poke poke poke)?
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If I make the fold INLINABLE, it doesn't actually seem to do anything. If I make it INLINE, I get pokes up to around 32 elements, which suggests some judgement has been used. Unfortunately, going bigger seems to lead to some useless code duplication. So we might be better off just choosing our own cutoff, whatever that should be (currently set to 1, essentially). Another reasonable option would be to just leave it as I have it right now and push GHC for array literals or something.
Closes haskell#331
Pinning an array the user wants unpinned is much less likely to break code than failing to pin one the user wants pinned.
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Thanks, @phadej! I'll merge. |
Closes #331