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diff --git a/docs/users_guide/glasgow_exts.xml b/docs/users_guide/glasgow_exts.xml
index e42bf79..ff32cc2 100644
--- a/docs/users_guide/glasgow_exts.xml
+++ b/docs/users_guide/glasgow_exts.xml
@@ -323,11 +323,11 @@ became out of date, and wrong information is worse than none.
The Real Truth about what primitive types there are, and what operations
work over those types, is held in the file
-fptools/ghc/compiler/prelude/primops.txt.pp.
+compiler/prelude/primops.txt.pp.
This file is used directly to generate GHC's primitive-operation definitions, so
it is always correct! It is also intended for processing into text.
- Indeed,
+Indeed,
the result of such processing is part of the description of the
External
@@ -366,6 +366,20 @@ would use in C: Int# (long int),
know and love—usually one instruction.
+ For some primitive types we have special syntax for literals.
+Anything that would be an integer lexeme followed by a
+# is an Int# literal, e.g.
+32# and -0x3A#. Likewise,
+any non-negative integer literal followed by
+## is a Word# literal.
+Likewise, any floating point literal followed by a
+# is a Float# literal, and
+followed by ## is a
+Double#. Finally, a string literal followed by a
+#, e.g. "foo"#,
+is a Addr# literal.
+
+
Primitive (unboxed) types cannot be defined in Haskell, and are
therefore built into the language and compiler. Primitive types are
@@ -6046,7 +6060,8 @@ Assertion failures can be caught, see the documentation for the
word that GHC understands are described
in the following sections; any pragma encountered with an
unrecognised word is (silently)
- ignored.
+ ignored. The layout rule applies in pragmas, so the closing #-}
+ should start in a column to the right of the opening {-#.
Certain pragmas are file-header pragmas. A file-header
pragma must precede the module keyword in the file.
@@ -6598,10 +6613,9 @@ Here is an example:
{-# RULES
- "map/map" forall f g xs. map f (map g xs) = map (f.g) xs
- #-}
+ "map/map" forall f g xs. map f (map g xs) = map (f.g) xs
+ #-}
-
@@ -6611,15 +6625,32 @@ Here is an example:
From a syntactic point of view:
-
+
- There may be zero or more rules in a RULES pragma.
+ There may be zero or more rules in a RULES pragma, separated by semicolons (which
+ may be generated by the layout rule).
+
+The layout rule applies in a pragma.
+Currently no new indentation level
+is set, so if you put several rules in single RULES pragma and wish to use layout to separate them,
+you must lay out the starting in the same column as the enclosing definitions.
+
+ {-# RULES
+ "map/map" forall f g xs. map f (map g xs) = map (f.g) xs
+ "map/append" forall f xs ys. map f (xs ++ ys) = map f xs ++ map f ys
+ #-}
+
+Furthermore, the closing #-}
+should start in a column to the right of the opening {-#.
+
+
+
Each rule has a name, enclosed in double quotes. The name itself has
no significance at all. It is only used when reporting how many times the rule fired.
@@ -6633,7 +6664,7 @@ immediately after the name of the rule. Thus:
{-# RULES
"map/map" [2] forall f g xs. map f (map g xs) = map (f.g) xs
- #-}
+ #-}
The "[2]" means that the rule is active in Phase 2 and subsequent phases. The inverse
notation "[~2]" is also accepted, meaning that the rule is active up to, but not including,
@@ -6642,17 +6673,8 @@ Phase 2.
-
-
-
- Layout applies in a RULES pragma. Currently no new indentation level
-is set, so you must lay out your rules starting in the same column as the
-enclosing definitions.
-
-
-
Each variable mentioned in a rule must either be in scope (e.g. map),
or bound by the forall (e.g. f, g, xs). The variables bound by