Add an extension to disable n+k patterns

[ghc-hetmet.git] / docs / users_guide / glasgow_exts.xml

diff --git a/docs/users_guide/glasgow_exts.xml b/docs/users_guide/glasgow_exts.xml
index c0feb5b..ea31390 100644 (file)
--- a/docs/users_guide/glasgow_exts.xml
+++ b/docs/users_guide/glasgow_exts.xml
@@ -840,6 +840,19 @@ y)</literal> will not be coalesced.
 
 </sect2>
 
+    <!-- ===================== n+k patterns ===================  -->
+
+<sect2 id="n-k-patterns">
+<title>n+k patterns</title>
+<indexterm><primary><option>-XNoNPlusKPatterns</option></primary></indexterm>
+
+<para>
+<literal>n+k</literal> pattern support is enabled by default. To disable
+it, you can use the <option>-XNoNPlusKPatterns</option> flag.
+</para>
+
+</sect2>
+
     <!-- ===================== Recursive do-notation ===================  -->
 
 <sect2 id="mdo-notation">