A fast Haskell library for parsing ByteStrings
Questions tagged [attoparsec]
131 questions
0
votes
1 answer
Multi-line *non* match with attoparsec
I was playing around with parsing (PostgreSQL) logs which can have entries that are multi-line.
2016-01-01 01:01:01 entry1
2016-01-01 01:01:02 entry2a
entry2b
2016-01-01 01:01:03 entry3
So - with a Perl or Python script I'd just grab the next…
Richard Huxton
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0
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1 answer
Attoparsec optional parser with Maybe result
I have an Attoparsec parser like this:
myParser :: Parser Text
myParser = char '"' *> takeWhile (not . isspace) <* char '"'
I want to make this parser optional so I get a function that returns Just txt if the parser matches and Nothing else, i.e. a…
Uli Köhler
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0
votes
1 answer
attoparsec: succeeding on part of the input instead of failing
I have an attoparsec parser, and tests for it, what annoys me is that if I comment part of the parser and run the tests, the parser doesn't return Left "parse error at line ..." but instead I get Right [].
Note that I'm using parseOnly to make it…
Emmanuel Touzery
- 9,008
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0
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1 answer
Conduit and Attoparsec - extracting delimited text
Say I have a document with text delimited by Jade-style brackets, like {{foo}}. I've written an Attoparsec parser that seems to extract foo properly:
findFoos :: Parser [T.Text]
findFoos = many $ do
manyTill anyChar (string "{{")
manyTill letter…
Athan Clark
- 3,886
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0
votes
1 answer
Manually terminate inputs for Conduit Attoparsec
I am processing a syslog logfile, each line as an individual syslog entry, and parsing that entry using a Attoparsec parser. So I am using
fileToBS :: IO Handle -> C.Source (ResourceT IO) BS.ByteString
fileToBS handleMaker = source C.$=…
xrl
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0
votes
1 answer
Haskell parse list of integers with Attoparsec
I need some help parsing a list of comma delimited integers from a file, when the list of integers can be any length. The string might look like "1,2,3,4,5,6,7,8,..." and the list I need made would be like [1,2,3,4,5,6,7,8,...].
The file format…
user3638162
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0
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1 answer
Parsing CSV header into list of parsers
I want to parse first line of CSV file and to get list of parsers as a result, and fail miserably.
After some simplifications I got code I think should work, but it does not, and I don't understand why.
Here it is:
{-# LANGUAGE OverloadedStrings…
Alexander Kusev
- 63
- 1
- 5
0
votes
1 answer
Out of Memory Using Attoparsec
I'm trying to make a simple parser with attoparsec. The production rules are along the lines of:
block: ?token> [inline]
inline: foo | anyText
So, what I'm trying to get at is, a block starts with the literal ?, followed by a token,…
nomen
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0
votes
2 answers
Attoparsec compile errors
I am trying to learn to use attoparsec. I am trying to parse a text file of the following format:
id int
call_uuid string 30
My code is here:
{-# LANGUAGE OverloadedStrings #-}
import Control.Applicative ((<$>))
import Data.Char (isDigit,…
donatello
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0
votes
2 answers
Trying to simplify the checking of an IO Bool in an Attoparsec parser
I'm trying to simplify the below code that's part of an attoparsec parser for a network packet, and I'm at a loss for a nice way to do it.
It starts with a call to atEnd :: IO Bool to determine if there's more to parse. I can't find a nicer way to…
jhickner
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-2
votes
2 answers
how to parse yahoo historical csv with Attoparsec
i am a beginner of haskell, how to parse with attoparsec into open array, high array etc
module CsvParser (
Quote (..)
, csvFile
, quote
) where
import System.IO
import Data.Attoparsec.Text
import Data.Attoparsec.Combinator
import…
Moyes
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