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diff --git a/docs/users_guide/glasgow_exts.xml b/docs/users_guide/glasgow_exts.xml
index f8cd504..aeb9314 100644
--- a/docs/users_guide/glasgow_exts.xml
+++ b/docs/users_guide/glasgow_exts.xml
@@ -56,38 +56,7 @@ documentation describes all the libraries that come with GHC.
The flag
is equivalent to enabling the following extensions:
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- ,
- .
+ &what_glasgow_exts_does;
Enabling these options is the only
effect of .
We are trying to move away from this portmanteau flag,
@@ -1894,6 +1863,26 @@ not * then an explicit kind annotation must be used
Nevertheless, they can be useful when defining "phantom types".
+
+Data type contexts
+
+Haskell allows datatypes to be given contexts, e.g.
+
+
+data Eq a => Set a = NilSet | ConsSet a (Set a)
+
+
+give constructors with types:
+
+
+NilSet :: Set a
+ConsSet :: Eq a => a -> Set a -> Set a
+
+
+In GHC this feature is an extension called
+DatatypeContexts, and on by default.
+
+
Infix type constructors, classes, and type variables
@@ -7475,7 +7464,7 @@ Assertion failures can be caught, see the documentation for the
A list of all supported language extensions can be obtained by invoking
- ghc --supported-languages (see ).
+ ghc --supported-extensions (see ).
Any extension from the Extension type defined in