From 16c882b501cfc56ae3082ae688891e914a02d5dc Mon Sep 17 00:00:00 2001
From: darkf <lw9k123@gmail.com>
Date: Sat, 19 Oct 2013 02:05:16 -0700
Subject: [PATCH] add cons pattern to parser

---
 parser.hs | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/parser.hs b/parser.hs
index 8664a6a..c87ae2e 100644
--- a/parser.hs
+++ b/parser.hs
@@ -39,9 +39,19 @@ block = do
 	reserved "end"
 	return $ Block lst
 
+intPattern = fmap IntP integer
+varPattern = fmap VarP identifier
+
+consPattern = do
+	x <- intPattern <|> varPattern
+	symbol "::"
+	y <- pattern
+	return $ ConsP x y
+
 pattern = option UnitP $
-	        fmap VarP identifier
-	    <|> fmap IntP integer
+			try consPattern
+	    <|> varPattern
+	    <|> intPattern
 
 patterns = sepBy pattern (symbol ",")