Moved Thue parser into its own module

1 files changed, 79 insertions, 0 deletions

diff --git a/Thue/Parser.hs b/Thue/Parser.hs
new file mode 100644
index 0000000..dd40e23
--- /dev/null
+++ b/Thue/Parser.hs
@@ -0,0 +1,79 @@
+module Parser (
+	ThueProgram(..),
+	Rule(..),
+	State,
+
+	parseThue
+	) where
+
+import Text.ParserCombinators.Parsec
+
+
+
+data ThueProgram = ThueProgram { thueRules :: [Rule]
+                               , thueInitialState :: State }
+    deriving (Show)
+
+
+data Rule = Rule { original :: State
+                 , replacement :: State }
+    deriving (Show)
+
+
+type State = String
+
+
+
+
+parseThue :: String -> Either ParseError ThueProgram
+parseThue = parse thue "error"
+
+
+
+
+thue = do
+	rs <- many rule
+	separatorLine
+	i <- initialState
+	eof
+	return (ThueProgram rs i)
+
+
+rule = do
+	o <- ruleState
+	separator
+	r <- state
+	eol
+	return (Rule o r)
+
+
+separatorLine = whiteSpace >> separator >> whiteSpace >> eol
+separator = string "::="
+
+
+initialState = do
+	s <- state `sepEndBy` eol
+	return (concat s)
+
+
+ruleState = many ruleStateChar
+
+
+ruleStateChar  =  noneOf "\n\r:"
+	          <|> try (do { char ':'; notFollowedBy (string ":="); return ':'})
+
+
+state = many stateChar
+
+
+stateChar = noneOf "\n\r"
+
+
+whiteSpace = many (oneOf "\t ")
+
+
+eol  =  try (string "\r\n")
+    <|> try (string "\n\r")
+    <|> try (string "\r")
+    <|> try (string "\n")
+