diff -r d923ba9d1145 -r 3774ac58e65e tools/pas2c/PascalParser.hs
--- a/tools/pas2c/PascalParser.hs	Sat Jun 15 23:44:37 2013 +0400
+++ b/tools/pas2c/PascalParser.hs	Sat Jun 15 23:45:53 2013 +0400
@@ -24,9 +24,10 @@
     return u
 
 iD = do
-    i <- liftM (flip Identifier BTUnknown) (identifier pas)
+    i <- identifier pas
     comments
-    return i
+    when (i == "not") $ unexpected "'not' used as an identifier"
+    return $ Identifier i BTUnknown
 
 unit = do
     string "unit" >> comments