src/Text/Hakyll/CompressCSS.hs · hakyll

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hakyll/src/Text/Hakyll/CompressCSS.hs

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1module Text.Hakyll.CompressCSS

2 ( compressCSS

3 ) where

5import Data.List

6import Text.Regex

8-- | Compress CSS to speed up your site.

9compressCSS :: String -> String

10compressCSS = compressSeparators

11 . compressWhitespace

12 . stripComments

14-- | Compresses certain forms of separators.

15compressSeparators :: String -> String

16compressSeparators str = subRegex (mkRegex "\\s*([;:])\\s*") str "\\1"

18-- | Compresses all whitespace.

19compressWhitespace :: String -> String

20compressWhitespace str = subRegex (mkRegex "\\s\\s*") str " "

22-- | Function that strips CSS comments away.

23stripComments :: String -> String

24stripComments [] = []

25stripComments str | isPrefixOf "/*" str = stripComments $ eatComments $ drop 2 str

26 | otherwise = (head str) : (stripComments $ tail str)

27 where eatComments str' | null str' = []

28 | isPrefixOf "*/" str' = drop 2 str'

29 | otherwise = eatComments $ tail str'