# bitset-word8

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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`.

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

You can create pre-evaluated set using Template Haskell.

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

myPreEvaluatedCharSet :: BitSetWord8
myPreEvaluatedCharSet = $(lift myCharSet)
```

### Example Usage

```haskell
import Data.Attoparsec.ByteString

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