Dear all

the runnable example code is as blow

===================================================================

import Conduit

import Text.Regex (matchRegex,mkRegex,Regex)

loghead = mkRegex "^([0-9]{4}-[0-9]{2}-[0-9]{2} [0-9]{2}:[0-9]{2}:[0-9]{2},[0-9]{3} )"

-- "2015-01-25 00:04:18,840"

logMerge::Regex->String->String->(String,[String])

logMerge logregex str accum =

case matchRegex logregex str of

Just _ -> (str,[(accum++"\n")])

Nothing -> case null accum of

True -> (str,[])

False -> (accum ++ " " ++ str,[])

runMerge::String->String->IO ()

runMerge infile outfile =

runResourceT $ sourceFile infile $= linesUnboundedC $= concatMapAccumC (logMerge loghead ) "" $$ sinkFile outfile

================================================================

the example input file is

---------

2015-01-25 00:03:44,331 | DEBUG | WebContainer : 20 | | errorCode: toString() = null

2015-01-25 00:03:44,331 | DEBUG | WebContainer : 20 | codsexception.getErrorCode(): toString()

{

errorCode = "UNEXPECTED_PROBLEM"

severity = ""

}

2015-01-25 00:03:44,331 | DEBUG | WebContainer : 20 | |

2015-01-25 00:03:45,331 | DEBUG | WebContainer : 20 | |

---------

the expected output is

---------

2015-01-25 00:03:44,331 | DEBUG | WebContainer : 20 | | errorCode: toString() = null

2015-01-25 00:03:44,331 | DEBUG | WebContainer : 20 | codsexception.getErrorCode(): toString() { errorCode = "UNEXPECTED_PROBLEM" severity = "" }

2015-01-25 00:03:44,331 | DEBUG | WebContainer : 20 | |

2015-01-25 00:03:45,331 | DEBUG | WebContainer : 20 | |

---------

the actual output is blow, missing the last line of log

---------

2015-01-25 00:03:44,331 | DEBUG | WebContainer : 20 | | errorCode: toString() = null

2015-01-25 00:03:44,331 | DEBUG | WebContainer : 20 | codsexception.getErrorCode(): toString() { errorCode = "UNEXPECTED_PROBLEM" severity = "" }

2015-01-25 00:03:44,331 | DEBUG | WebContainer : 20 | |

---------

Thanks

在 2017年7月19日，下午7:50，Michael Snoyman <michael@snoyman.com> 写道：

I'm afraid I doon't follow what it meant by the stream here. Could you provide a complete, runnable example and indicate what the expected and actual output are?

On Mon, Jul 17, 2017 at 5:48 AM, jun zhang <zhangjun.julian@gmail.com> wrote:
Dear cafes

I use Conduit to parse a huge file. And I need merge lines by condition.

I find the concatMapAccumC can do that and I write a demo as blow(with conduit-combinators-1.0.6,lts-6.18).
The problem is if the last item didn’t make condition true, the data only keep in the accum but missing in stream.

Any one can give me some advises?

Thanks

----------------------------
import Conduit

test'::Int->Int->(Int,[Int])
test' a s = case (a+s) > 5 of
True -> (0,[a+s])
False -> (a+s,[])

testlog::IO [Int]
testlog = runConduit $ (yieldMany [1,2,3,4,5,6,3]) $= (concatMapAccumC test' 0 ) $$ sinkList

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