X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Futils%2FFastString.lhs;h=8dbfefaa0b7690aae3b1a43b8814205c079e841e;hb=423d477bfecd490de1449c59325c8776f91d7aac;hp=d46b77599657daab35ae660248895a09d5889fbd;hpb=553e90d9a32ee1b1809430f260c401cc4169c6c7;p=ghc-hetmet.git

diff --git a/ghc/compiler/utils/FastString.lhs b/ghc/compiler/utils/FastString.lhs
index d46b775..8dbfefa 100644
--- a/ghc/compiler/utils/FastString.lhs
+++ b/ghc/compiler/utils/FastString.lhs
@@ -3,8 +3,18 @@
 %
 \section{Fast strings}
 
-Compact representations of character strings with
-unique identifiers (hash-cons'ish).
+FastString:	A compact, hash-consed, representation of character strings.
+		Comparison is O(1), and you can get a Unique from them.
+		Generated by the FSLIT macro
+		Turn into SDoc with Outputable.ftext
+
+LitString:	Just a wrapper for the Addr# of a C string (Ptr CChar).
+		Practically no operations
+		Outputing them is fast
+		Generated by the SLIT macro
+		Turn into SDoc with Outputable.ptext
+
+Use LitString unless you want the facilities of FastString
 
 \begin{code}
 module FastString
@@ -498,7 +508,6 @@ hPutFS handle (UnicodeStr _ is)
 -- LitStrings, here for convenience only.
 
 type LitString = Ptr ()
--- ToDo: make it a Ptr when we don't have to support 4.08 any more
 
 mkLitString# :: Addr# -> LitString
 mkLitString# a# = Ptr a#