bitset-word8: Space efficient set of Word8 and some pre-canned sets useful for parsing HTTP

[ concurrency, library, mit ] [ Propose Tags ]

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Dependencies base (>=4.7 && <5), containers, template-haskell, th-lift-instances [details]
License MIT
Copyright 2017-2020 Naoto Shimazaki
Author Naoto Shimazaki
Category Concurrency
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Source repo head: git clone
Uploaded by nshimaza at 2020-07-28T06:26:55Z
Distributions LTSHaskell:, NixOS:, Stackage:
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Last success reported on 2020-07-28 [all 1 reports]


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Readme for bitset-word8-

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License: MIT Build Status Hackage Stackage Nightly Stackage LTS

Space efficient set of Word8 and some pre-canned sets useful for parsing HTTP related ByteString. This package is intended to provide O(1) membership test on any subset of ASCII and Latin-1 character set in order to write efficient HTTP related parser.

Creating your own set

You can create your own set by fromList.

myCharSet :: BitSetWord8
myCharSet = fromList [ 'Y', 'y', 'N', 'n' ]

You can create pre-evaluated set using Template Haskell.

{-# LANGUAGE TemplateHaskell #-}
import Language.Haskell.TH.Syntax (Lift, lift)

myPreEvaluatedCharSet :: BitSetWord8
myPreEvaluatedCharSet = $(lift myCharSet)

Example Usage

import Data.Attoparsec.ByteString

-- | Parse RFC7230 token.
token :: Parser ByteString
token = takeWhile1 (member rfc7230TChar)