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src/Data/SExpresso/Parse/Location.hs:47:12: error:
    • Could not deduce (TraversableStream s)
        arising from a use of ‘getSourcePos’
      from the context: MonadParsec e s m
        bound by the type signature for:
                   located :: forall e s (m :: * -> *) a.
                              MonadParsec e s m =>
                              m a -> m (Located a)
        at src/Data/SExpresso/Parse/Location.hs:45:1-54
      Possible fix:
        add (TraversableStream s) to the context of
          the type signature for:
            located :: forall e s (m :: * -> *) a.
                       MonadParsec e s m =>
                       m a -> m (Located a)
    • In a stmt of a 'do' block: begin <- getSourcePos
      In the expression:
        do begin <- getSourcePos
           result <- parser
           end <- getSourcePos
           return $ At (Span begin end) result
      In an equation for ‘located’:
          located parser
            = do begin <- getSourcePos
                 result <- parser
                 end <- getSourcePos
                 ....
   |
47 |   begin <- getSourcePos
   |

import Data.Void {- base -}

import qualified Text.Megaparsec as M {- megaparsec -}

import qualified Data.SExpresso.Parse as S {- sexpresso -}
import qualified Data.SExpresso.SExpr as S {- sexpresso -}
import qualified Data.SExpresso.Language.SchemeR5RS as S {- sexpresso -}

-- > parse_sexp "-1"
parse_sexp :: String -> Either (M.ParseErrorBundle String Void) [S.SExpr S.SExprType S.SchemeToken]
parse_sexp = M.parse (S.decode S.sexpr) ""