Visualizations

REs and Parsers can be visualized using Regex.Internal.Debug. Here are some examples.

URI

>>> import Control.Applicative
>>> import qualified Regex.List as R
>>> import qualified Data.CharSet as CS
>>> :{
data URI = URI
  { scheme    :: Maybe String
  , authority :: Maybe String
  , path      :: String
  , query     :: Maybe String
  , fragment  :: Maybe String
  } deriving Show
:}
>>> :{
uriRE :: R.RE Char URI
uriRE = URI
  <$> optional (R.someStringOf (CS.not ":/?#") <* R.single ':')
  <*> optional (R.list "//" *> R.manyStringOf (CS.not "/?#"))
  <*> R.manyStringOf (CS.not "?#")
  <*> optional (R.single '?' *> R.manyStringOf (CS.not "#"))
  <*> optional (R.single '#' *> R.manyList)
:}
>>>
>>> import Regex.Internal.Debug
>>> writeFile "uri.dot" $ reToDot (Just (CS.elems CS.ascii, dispCharRanges)) uriRE
>>> writeFile "uri_p.dot" $ parserToDot (Just (CS.elems CS.ascii, dispCharRanges)) (R.compile uriRE)
>>> writeFile "uri_p_ignore.dot" $ parserToDot (Just (CS.elems CS.ascii, dispCharRanges)) (R.compile (() <$ uriRE))
>>> :! dot -Tpng -o uri.png uri.dot
>>> :! dot -Tpng -o uri_p.png uri_p.dot
>>> :! dot -Tpng -o uri_p_ignore.png uri_p_ignore.dot

uri.png

uri_p.png

uri_p_ignore.png

Int range

>>> import qualified Regex.List as R
>>> import qualified Data.CharSet as CS
>>> re = R.intRangeDec (pure ()) (123,4567)
>>> writeFile "num.dot" $ reToDot (Just (CS.elems CS.ascii, dispCharRanges)) re
>>> writeFile "num_p.dot" $ parserToDot (Just (CS.elems CS.ascii, dispCharRanges)) (R.compile re)
>>> writeFile "num_p_ignore.dot" $ parserToDot (Just (CS.elems CS.ascii, dispCharRanges)) (R.compile (() <$ re))
>>> :! dot -Tpng -o num.png num.dot
>>> :! dot -Tpng -o num_p.png num_p.dot
>>> :! dot -Tpng -o num_p_ignore.png num_p_ignore.dot

num.png

num_p.png

num_p_ignore.png