adba0595bd
This is needed because when preferred content matches on files, the second pass would otherwise want to drop all keys. Using a bloom filter avoids this, and in the case of a false positive, a key will be left undropped that preferred content would allow dropping. Chances of that happening are a mere 1 in 1 million.
67 lines
1.3 KiB
Haskell
67 lines
1.3 KiB
Haskell
{- bloomfilter compatability wrapper
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-
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- Copyright 2014 Joey Hess <id@joeyh.name>
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-
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- License: BSD-2-clause
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-}
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{-# LANGUAGE CPP #-}
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module Utility.Bloom (
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Bloom,
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safeSuggestSizing,
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Hashable(..),
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cheapHashes,
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elemB,
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notElemB,
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newMB,
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insertMB,
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unsafeFreezeMB,
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) where
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#if MIN_VERSION_bloomfilter(2,0,0)
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import qualified Data.BloomFilter.Mutable as MBloom
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import qualified Data.BloomFilter as Bloom
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#else
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import qualified Data.BloomFilter as Bloom
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#endif
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import Data.BloomFilter.Easy (safeSuggestSizing, Bloom)
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import Data.BloomFilter.Hash (Hashable(..), cheapHashes)
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import Control.Monad.ST (ST)
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#if MIN_VERSION_bloomfilter(2,0,0)
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notElemB :: a -> Bloom a -> Bool
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notElemB = Bloom.notElem
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elemB :: a -> Bloom a -> Bool
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elemB = Bloom.elem
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newMB :: (a -> [Bloom.Hash]) -> Int -> ST s (MBloom.MBloom s a)
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newMB = MBloom.new
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insertMB :: MBloom.MBloom s a -> a -> ST s ()
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insertMB = MBloom.insert
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unsafeFreezeMB :: MBloom.MBloom s a -> ST s (Bloom a)
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unsafeFreezeMB = Bloom.unsafeFreeze
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#else
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notElemB :: a -> Bloom a -> Bool
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notElemB = Bloom.notElemB
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elemB :: a -> Bloom a -> Bool
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elemB = Bloom.elem
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newMB :: (a -> [Bloom.Hash]) -> Int -> ST s (Bloom.MBloom s a)
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newMB = Bloom.newMB
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insertMB :: Bloom.MBloom s a -> a -> ST s ()
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insertMB = Bloom.insertMB
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unsafeFreezeMB :: Bloom.MBloom s a -> ST s (Bloom a)
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unsafeFreezeMB = Bloom.unsafeFreezeMB
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#endif
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