lambda for HM

[fp.git] / src / Lambda / Parser / Fancy.hs

diff --git a/src/Lambda/Parser/Fancy.hs b/src/Lambda/Parser/Fancy.hs
index 10231b8..f7a523d 100644 (file)
--- a/src/Lambda/Parser/Fancy.hs
+++ b/src/Lambda/Parser/Fancy.hs
@@ -9,15 +9,20 @@
 -- Maintainer  :  tomik.musil@gmail.com
 -- Stability   :  experimental
 --
 -- Maintainer  :  tomik.musil@gmail.com
 -- Stability   :  experimental
 --

--- Parser for λ-terms. '.' in λ implies brackets to the end of the context.
+-- Parser for λ-terms. \'.\' in λ implies brackets to the end of the context.

 
 -- TODO: proper documentation
 
 module Lambda.Parser.Fancy 
 
 -- TODO: proper documentation
 
 module Lambda.Parser.Fancy 

-  ( tRead
+  (
+  -- * Main parser
+    tRead

   , parseTerm
   , parseTerm

+  -- * Auxiliary parsers
+  , parseVar

   )  where
 
   )  where
 

+import Data.Char (isAsciiLower)

 import Data.Text as T hiding (map)
 import Data.Attoparsec.Text
 import Control.Applicative
 import Data.Text as T hiding (map)
 import Data.Attoparsec.Text
 import Control.Applicative


@@ -52,12 +57,12 @@ tRead s = case parseOnly (parseTerm <* endOfInput) (T.pack s) of
 
 parseVar :: Parser Term
 parseVar = do
 
 parseVar :: Parser Term
 parseVar = do

-  x <- many1 (letter <|> digit)
+  x <- many1 letter

   return $! Var x
 
 parseLambda :: Parser Term
 parseLambda = do
   return $! Var x
 
 parseLambda :: Parser Term
 parseLambda = do

-  char '\\' <|> char 'λ'
+  char '\\' <|> char 'λ' <|> char 'L'

   vars <- sepBy1 parseVar (char ' ')
   char '.'
   t <- parseTerm
   vars <- sepBy1 parseVar (char ' ')
   char '.'
   t <- parseTerm