X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2FhsSyn%2FHsLit.lhs;h=c29083c63b75325578838b7c82e2297ce28268be;hp=9a0e8750e6bdf8193faf56f93850585407fe9e27;hb=478e69b303eb2e653a2ebf5c888b5efdfef1fb9d;hpb=703ca1542c8e0983cc9d8eebce6e9f3dd3fd71e2

diff --git a/compiler/hsSyn/HsLit.lhs b/compiler/hsSyn/HsLit.lhs
index 9a0e875..c29083c 100644
--- a/compiler/hsSyn/HsLit.lhs
+++ b/compiler/hsSyn/HsLit.lhs
@@ -5,6 +5,8 @@
 \section[HsLit]{Abstract syntax: source-language literals}
 
 \begin{code}
+{-# LANGUAGE DeriveDataTypeable #-}
+
 module HsLit where
 
 #include "HsVersions.h"
@@ -14,6 +16,8 @@ import HsTypes (PostTcType)
 import Type	( Type )
 import Outputable
 import FastString
+
+import Data.Data
 \end{code}
 
 
@@ -40,6 +44,7 @@ data HsLit
 					-- 	(overloaded literals are done with HsOverLit)
   | HsFloatPrim	    Rational		-- Unboxed Float
   | HsDoublePrim    Rational		-- Unboxed Double
+  deriving (Data, Typeable)
 
 instance Eq HsLit where
   (HsChar x1)	    == (HsChar x2)	 = x1==x2
@@ -58,20 +63,34 @@ instance Eq HsLit where
 data HsOverLit id 	-- An overloaded literal
   = OverLit {
 	ol_val :: OverLitVal, 
-	ol_rebindable :: Bool,		-- True <=> rebindable syntax
-					-- False <=> standard syntax
+	ol_rebindable :: Bool,		-- 
 	ol_witness :: SyntaxExpr id,	-- Note [Overloaded literal witnesses]
 	ol_type :: PostTcType }
+  deriving (Data, Typeable)
 
 data OverLitVal
   = HsIntegral   !Integer   	-- Integer-looking literals;
   | HsFractional !Rational   	-- Frac-looking literals
   | HsIsString   !FastString 	-- String-looking literals
+  deriving (Data, Typeable)
 
 overLitType :: HsOverLit a -> Type
 overLitType = ol_type
 \end{code}
 
+Note [ol_rebindable]
+~~~~~~~~~~~~~~~~~~~~
+The ol_rebindable field is True if this literal is actually 
+using rebindable syntax.  Specifically:
+
+  False iff ol_witness is the standard one
+  True  iff ol_witness is non-standard
+
+Equivalently it's True if
+  a) RebindableSyntax is on
+  b) the witness for fromInteger/fromRational/fromString
+     that happens to be in scope isn't the standard one
+
 Note [Overloaded literal witnesses]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *Before* type checking, the SyntaxExpr in an HsOverLit is the