b3fad05 · text · git.iko.soy

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Benchmark concatMap, and redefine it to not use fusion.

b3fad05Bryan O'Sullivan17 years ago

Data/Text.hs+2−5

@@ -574,12 +574,9 @@ concat ts = Text (A.run go) 0 len

574{-# INLINE concat #-}

575

576-- | /O(n)/ Map a function over a 'Text' that results in a 'Text', and

577−-- concatenate the results. Subject to fusion.

577+-- concatenate the results.

578−--

579−-- Note: if in 'concatMap' @f@ @t@, @f@ is defined in terms of fusible

580−-- functions, it will also be fusible.

581concatMap :: (Char -> Text) -> Text -> Text

578concatMap :: (Char -> Text) -> Text -> Text

582−concatMap f t = unstream (S.concatMap (stream . f) (stream t))

579+concatMap f = concat . foldr ((:) . f) []

583{-# INLINE concatMap #-}

580{-# INLINE concatMap #-}

584

581

585-- | /O(n)/ 'any' @p@ @t@ determines whether any character in the

582-- | /O(n)/ 'any' @p@ @t@ determines whether any character in the

tests/Benchmarks.hs+5

@@ -51,6 +51,11 @@ main = do

51 , bench "b8" $ nf B8.concat sl

52 , bench "list" $ nf L.concat ll

53 ],

54+ bgroup "concatMap" [

55+ bench "text" $ nf (T.concatMap (T.replicate 3 . T.singleton)) t0

56+ , bench "b8" $ nf (B8.concatMap (B8.replicate 3)) s0

57+ , bench "list" $ nf (L.concatMap (L.replicate 3 . (:[]))) l0

58+ ],

54 bgroup "decode" [

59 bgroup "decode" [

55 bench "text" $ nf decodeUtf8 s0

60 bench "text" $ nf decodeUtf8 s0

56 , bench "b8" $ nf B8.unpack s0

61 , bench "b8" $ nf B8.unpack s0