core/src/Text/Edifact/Common/Segments/UNA.hs

   1 module Text.Edifact.Common.Segments.UNA
   2  ( segmentUNA
   3  ) where
   4
   5 import           Text.Edifact.Parsing
   6 import           Text.Edifact.Parsing.Commons (updateSyntax)
   7 import           Text.Edifact.Types           (Syntax (..), defaultSyntax)
   8
   9 import           Control.Monad                (void)
  10 import           Text.Parsec                  (anyChar, char, endOfLine,
  11                                                optionMaybe, string, try)
  12 import qualified Text.Parsec                  as P (optional)
  13
  14 segmentUNA :: Parser ()
  15 segmentUNA =
  16   let segmentParser = string "UNA" *> parseSyntax <* P.optional endOfLine
  17       nothing = pure ()
  18   in  optionMaybe (try segmentParser) >>= maybe nothing updateSyntax
  19
  20 parseSyntax :: Parser Syntax
  21 parseSyntax = do
  22   compositeSeparator' <- anyChar
  23   elementSeparator'   <- anyChar
  24   decimalSign'        <- anyChar
  25   escape'             <- anyChar
  26   void $ char ' ' -- reserved, not used
  27   segmentSeparator'   <- anyChar
  28   pure defaultSyntax
  29     { compositeSeparator = compositeSeparator'
  30     , elementSeparator   = elementSeparator'
  31     , decimalSign        = decimalSign'
  32     , escape             = escape'
  33     , segmentSeparator   = segmentSeparator'
  34     }