oh my god

src/Rlp/Lex.x

@@ -1,5 +1,5 @@
 {
-{-# LANGUAGE ViewPatterns, LambdaCase #-}
+{-# LANGUAGE ViewPatterns #-}
 {-# LANGUAGE GeneralisedNewtypeDeriving #-}
 {-# LANGUAGE OverloadedStrings #-}
 module Rlp.Lex
@@ -39,20 +39,10 @@ $nl             = [\n\r]
 $white_no_nl    = $white # $nl
 
 $namechar       = [$alpha $digit \' \#]
-$reservedsym    = [\(\)\,\;\[\]\`\{\}]
-$asciisym       = [\!\#\$\%\&\*\+\.\/\<\=\>\?\@\\\^\|\-\~\:]
-$namesym        = $asciisym # \;
 
-@reservedop =
-    "=" | \\ | "->" | "::" | "|"
+@varname        = $lower $namechar*
 
-@varname   = $lower $namechar*
-@conname   = $upper $namechar*
-@varsym    = $namesym+
-@consym    = \: $namesym*
-
-
-@decimal   = $digit+
+@digits         = $digit+
 
 rlp :-
     
@@ -65,8 +55,8 @@ rlp :-
 {
     \n                  { beginPush bol }
     @varname            { tokenWith TokenVarName }
-    @decimal            { tokenWith (TokenLitInt . readInt) }
-    @reservedop         { tokenWith readReservedOp }
+    @digits             { tokenWith (TokenLitInt . readInt) }
+    "="                 { constToken TokenEquals }
 }
 
 -- control characters
@@ -96,14 +86,6 @@ rlp :-
 
 {
 
-readReservedOp :: Text -> RlpToken
-readReservedOp = \case
-    "="     -> TokenEquals
-    "\\"    -> TokenLambda
-    "->"    -> TokenArrow
-    "::"    -> TokenHasType
-    s       -> error (show s)
-
 -- | @andBegin@, with the subtle difference that the start code is set
 --   /after/ the action
 thenBegin :: LexerAction a -> Int -> LexerAction a
@@ -145,12 +127,6 @@ alexGetByte inp = case inp ^. aiBytes of
 getInput :: P AlexInput
 getInput = use psInput
 
-takeInput :: Int -> AlexInput -> Text
-takeInput n inp = T.cons c cs
-    where
-        c = inp ^. aiPrevChar
-        cs = T.take (max 0 (n-1)) $ inp ^. aiSource
-
 getLexState :: P Int
 getLexState = use (psLexState . singular _head)
 
@@ -172,8 +148,8 @@ constToken t inp l = do
 tokenWith :: (Text -> RlpToken) -> LexerAction (Located RlpToken)
 tokenWith tf inp l = do
     pos <- getPos
-    let t = takeInput l inp
-    pure (Located (pos,l) (tf t))
+    let t = tf (T.take l $ inp ^. aiSource)
+    pure (Located (pos,l) t)
 
 getPos :: P Position
 getPos = use (psInput . aiPos)
@@ -200,10 +176,10 @@ initParseState s = ParseState
     }
 
 initAlexInput :: Text -> AlexInput
-initAlexInput t = AlexInput
-    { _aiPrevChar   = c
+initAlexInput s = AlexInput
+    { _aiPrevChar   = '\0'
     , _aiSource     = s
-    , _aiBytes      = b
+    , _aiBytes      = []
     , _aiPos        = (1,1)
     }