Merge branch 'master' of darcs.haskell.org:/srv/darcs//ghc

2 files changed, 54 insertions, 0 deletions

diff --git a/docs/users_guide/flags.xml b/docs/users_guide/flags.xml
index bb7ae45ba8..7cbeeab551 100644
--- a/docs/users_guide/flags.xml
+++ b/docs/users_guide/flags.xml
@@ -1122,6 +1122,18 @@
             <entry><option>-XNoPackageImports</option></entry>
           </row>
           <row>
+            <entry><option>-XLambdaCase</option></entry>
+            <entry>Enable <link linkend="lambda-case">lambda-case expressions</link>.</entry>
+            <entry>dynamic</entry>
+            <entry><option>-XNoLambdaCase</option></entry>
+          </row>
+          <row>
+            <entry><option>-XMultiWayIf</option></entry>
+            <entry>Enable <link linkend="multi-way-if">multi-way if-expressions</link>.</entry>
+            <entry>dynamic</entry>
+            <entry><option>-XNoMultiWayIf</option></entry>
+          </row>
+          <row>
             <entry><option>-XSafe</option></entry>
             <entry>Enable the <link linkend="safe-haskell">Safe Haskell</link> Safe mode.</entry>
             <entry>dynamic</entry>
diff --git a/docs/users_guide/glasgow_exts.xml b/docs/users_guide/glasgow_exts.xml
index df1ff2c181..dde235eda4 100644
--- a/docs/users_guide/glasgow_exts.xml
+++ b/docs/users_guide/glasgow_exts.xml
@@ -1669,6 +1669,48 @@ continues to stand for the unboxed singleton tuple data constructor.
 
 </sect2>
 
+<sect2 id="lambda-case">
+<title>Lambda-case</title>
+<para>
+The <option>-XLambdaCase</option> flag enables expressions of the form
+<programlisting>
+  \case { p1 -> e1; ...; pN -> eN }
+</programlisting>
+which is equivalent to
+<programlisting>
+  \freshName -> case freshName of { p1 -> e1; ...; pN -> eN }
+</programlisting>
+Note that <literal>\case</literal> starts a layout, so you can write
+<programlisting>
+  \case
+    p1 -> e1
+    ...
+    pN -> eN
+</programlisting>
+</para>
+</sect2>
+
+<sect2 id="multi-way-if">
+<title>Multi-way if-expressions</title>
+<para>
+With <option>-XMultiWayIf</option> flag GHC accepts conditional expressions
+with multiple branches:
+<programlisting>
+  if | guard1 -> expr1
+     | ...
+     | guardN -> exprN
+</programlisting>
+which is roughly equivalent to
+<programlisting>
+  case () of
+    _ | guard1 -> expr1
+    ...
+    _ | guardN -> exprN
+</programlisting>
+except that multi-way if-expressions do not alter the layout.
+</para>
+</sect2>
+
 <sect2 id="disambiguate-fields">
 <title>Record field disambiguation</title>
 <para>