Created
November 19, 2011 15:10
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iteratee implementation to print firstlines of files
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import Control.Monad | |
import Control.Monad.IO.Class | |
import Control.Applicative | |
import System.Environment | |
import System.Directory | |
import System.FilePath | |
import qualified Data.List as L | |
import qualified Data.ByteString as B | |
import qualified Data.Iteratee as I | |
import Data.Iteratee.Iteratee | |
import qualified Data.Iteratee.Char as EC | |
import qualified Data.Iteratee.IO.Fd as EIO | |
import qualified Data.Iteratee.ListLike as EL | |
getValidContents :: FilePath -> IO [String] | |
getValidContents path = | |
filter (`notElem` [".", "..", ".git", ".svn"]) | |
<$> getDirectoryContents path | |
isSearchableDir :: FilePath -> IO Bool | |
isSearchableDir dir = | |
(&&) <$> doesDirectoryExist dir | |
<*> (searchable <$> getPermissions dir) | |
getRecursiveContents :: FilePath -> IO [FilePath] | |
getRecursiveContents dir = do | |
cnts <- map (dir </>) <$> getValidContents dir | |
cnts' <- forM cnts $ \path -> do | |
isDirectory <- isSearchableDir path | |
if isDirectory | |
then getRecursiveContents path | |
else return [path] | |
return . concat $ cnts' | |
printI :: Iteratee [B.ByteString] IO () | |
printI = do | |
mx <- EL.tryHead | |
case mx of | |
Nothing -> return () | |
Just l -> do | |
liftIO . B.putStrLn $ l | |
printI | |
firstLineE :: Enumeratee [FilePath] [B.ByteString] IO () | |
firstLineE = mapChunksM $ \filenames -> do | |
forM filenames $ \filename -> do | |
i <- EIO.enumFile 1024 filename $ joinI $ ((mapChunks B.pack) ><> EC.enumLinesBS) EL.head | |
result <- run i | |
return result | |
enumDir :: FilePath -> Enumerator [FilePath] IO b | |
enumDir dir iter = runIter iter idoneM onCont | |
where | |
onCont k Nothing = do | |
(files, dirs) <- liftIO getFilesDirs | |
if null dirs | |
then return $ k (Chunk files) | |
else walk dirs $ k (Chunk files) | |
walk dirs = foldr1 (>>>) $ map enumDir dirs | |
getFilesDirs = do | |
cnts <- map (dir </>) <$> getValidContents dir | |
(,) <$> filterM doesFileExist cnts | |
<*> filterM isSearchableDir cnts | |
allFirstLines :: FilePath -> IO () | |
allFirstLines dir = do | |
i' <- enumDir dir $ joinI $ firstLineE printI | |
run i' | |
main = do | |
dir:_ <- getArgs | |
allFirstLines dir |
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import Control.Monad | |
import Control.Monad.IO.Class | |
import Control.Applicative | |
import System.Environment | |
import System.Directory | |
import System.FilePath | |
import qualified Data.List as L | |
import qualified Data.ByteString.Lazy.Char8 as B | |
getValidContents :: FilePath -> IO [String] | |
getValidContents path = | |
filter (`notElem` [".", "..", ".git", ".svn"]) | |
<$> getDirectoryContents path | |
isSearchableDir :: FilePath -> IO Bool | |
isSearchableDir dir = | |
(&&) <$> doesDirectoryExist dir | |
<*> (searchable <$> getPermissions dir) | |
getRecursiveContents :: FilePath -> IO [FilePath] | |
getRecursiveContents dir = do | |
cnts <- map (dir </>) <$> getValidContents dir | |
cnts' <- forM cnts $ \path -> do | |
isDirectory <- isSearchableDir path | |
if isDirectory | |
then getRecursiveContents path | |
else return [path] | |
return . concat $ cnts' | |
firstLine :: FilePath -> IO B.ByteString | |
firstLine file = do | |
b <- B.readFile file | |
return $ head . B.lines $ b | |
allFirstLines :: FilePath -> IO () | |
allFirstLines dir = do | |
filepaths <- getRecursiveContents dir | |
l <- mapM firstLine $ filepaths | |
mapM_ B.putStrLn l | |
main = do | |
dir:_ <- getArgs | |
allFirstLines dir |
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import Control.Monad | |
import System.Directory | |
import System.Environment | |
layer :: Int -> IO () | |
layer depth = do | |
if (depth <= 0) | |
then do mapM_ (flip writeFile "b!") (map show [1..2]) | |
return () | |
else do createDirectory "0" | |
setCurrentDirectory "0" | |
layer $ depth-1 | |
setCurrentDirectory ".." | |
createDirectory "1" | |
setCurrentDirectory "1" | |
layer $ depth-1 | |
setCurrentDirectory ".." | |
main = do | |
(dir:_) <- getArgs | |
setCurrentDirectory dir | |
putStrLn "creating ..." >> layer 10 >> putStrLn "done!" |
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.PHONY: clean test | |
test: allfirstlines_iteratee allfirstlines_naive gen_nuclear_test | |
bash run_test.sh | |
allfirstlines_naive: allfirstlines_naive.hs | |
ghc --make -rtsopts -O2 $@ | |
allfirstlines_iteratee: allfirstlines_iteratee.hs | |
ghc --make -rtsopts -O2 $@ | |
gen_nuclear_test: gen_nuclear_test.hs | |
ghc --make -O2 $@ | |
clean: | |
rm -f *.o *.hi | |
rm -rf test01/ test02/ test03/ |
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#!/usr/bin/bash | |
LOGDIR=log | |
mkdir -p $LOGDIR | |
ulimit -aS > $LOGDIR/ulimit_stat.log | |
if [[ ! -d test01 ]]; then | |
mkdir -p test01 | |
cd test01 | |
for f in $(seq 1 500) | |
do | |
echo $RANDOM > $f | |
done | |
cd .. | |
fi | |
./allfirstlines_naive test01/ +RTS -sstderr -RTS 2> $LOGDIR/allfirstlines_naive_test01.log 1>/dev/null | |
./allfirstlines_iteratee test01/ +RTS -sstderr -RTS 2> $LOGDIR/allfirstlines_iteratee_test01.log 1>/dev/null | |
if [[ ! -d test02 ]]; then | |
mkdir -p test02 | |
cd test02 | |
for f in $(seq 1 2048) | |
do | |
echo $RANDOM > $f | |
done | |
cd .. | |
fi | |
./allfirstlines_naive test02/ +RTS -sstderr -RTS 2> $LOGDIR/allfirstlines_naive_test02.log 1>/dev/null | |
./allfirstlines_iteratee test02/ +RTS -sstderr -RTS 2> $LOGDIR/allfirstlines_iteratee_test02.log 1>/dev/null | |
if [[ ! -d test03 ]]; then | |
mkdir -p test03 | |
./gen_nuclear_test test03 | |
fi | |
./allfirstlines_naive test03/ +RTS -sstderr -RTS 2> $LOGDIR/allfirstlines_naive_test03.log 1>/dev/null | |
./allfirstlines_iteratee test03/ +RTS -sstderr -RTS 2> $LOGDIR/allfirstlines_iteratee_test03.log 1>/dev/null |
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