New syntax for GADT-style record declarations, and associated refactoring

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

diff --git a/docs/users_guide/profiling.xml b/docs/users_guide/profiling.xml
index 51ae6f7..adb7a33 100644 (file)
--- a/docs/users_guide/profiling.xml
+++ b/docs/users_guide/profiling.xml
@@ -266,6 +266,22 @@ MAIN                     MAIN             0    0.0   0.0    100.0 100.0
       far to the right as possible when parsing. (SCC stands for "Set
       Cost Centre").</para>
 
+      <para>Here is an example of a program with a couple of SCCs:</para>
+
+<programlisting>
+main :: IO ()
+main = do let xs = {-# SCC "X" #-} [1..1000000]
+          let ys = {-# SCC "Y" #-} [1..2000000]
+          print $ last xs
+          print $ last $ init xs
+          print $ last ys
+          print $ last $ init ys
+</programlisting>
+
+      <para>which gives this heap profile when run:</para>
+
+      <imagedata fileref="prof_scc"/>
+
     </sect2>
 
     <sect2 id="prof-rules">