X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=docs%2Fusers_guide%2Fghci.xml;h=69078d5093ebb2e0489bf0d06d74a7f16594cdc1;hb=d62101efb9e263173b69fb89c07f03dcf805e81f;hp=c0167bfe09d924eb726d3183a3afe14b954854b2;hpb=66518f5de0f2f5076f06f2e037411985d96809e0;p=ghc-hetmet.git

diff --git a/docs/users_guide/ghci.xml b/docs/users_guide/ghci.xml
index c0167bf..69078d5 100644
--- a/docs/users_guide/ghci.xml
+++ b/docs/users_guide/ghci.xml
@@ -1106,10 +1106,14 @@ right :: [a]
 
       <para>Single-stepping is a great way to visualise the execution of your
         program, and it is also a useful tool for identifying the source of a
-        bug.  The concept is simple: single-stepping enables all the
-        breakpoints in the program and executes until the next breakpoint is
-        reached, at which point you can single-step again, or continue
-        normally.  For example:</para>
+        bug. GHCi offers two variants of stepping. Use 
+	<literal>:step</literal>  to enable all the
+        breakpoints in the program, and execute until the next breakpoint is
+        reached. Use <literal>:steplocal</literal> to limit the set
+	of enabled breakpoints to those in the current top level function.
+	Similarly, use <literal>:stepmodule</literal> to single step only on
+	breakpoints contained in the current module.
+	For example:</para>
 
 <screen>
 *Main> :step main
@@ -1118,10 +1122,11 @@ _result :: IO ()
 </screen>
 
       <para>The command <literal>:step
-          <replaceable>expr</replaceable></literal> begins the evaluation of
+        <replaceable>expr</replaceable></literal> begins the evaluation of
         <replaceable>expr</replaceable> in single-stepping mode.  If
         <replaceable>expr</replaceable> is ommitted, then it single-steps from
-        the current breakpoint.</para>
+        the current breakpoint. <literal>:stepover</literal> 
+        works similarly.</para>
 
       <para>The <literal>:list</literal> command is particularly useful when
         single-stepping, to see where you currently are:</para>
@@ -1923,6 +1928,12 @@ Prelude> :. cmds.ghci
 	  will be printed.  If <replaceable>name</replaceable> has
 	  been loaded from a source file, then GHCi will also display
 	  the location of its definition in the source.</para>
+	  <para>For types and classes, GHCi also summarises instances that
+	  mention them.  To avoid showing irrelevant information, an instance
+	  is shown only if (a) its head mentions <replaceable>name</replaceable>, 
+	  and (b) all the other things mentioned in the instance
+	  are in scope (either qualified or otherwise) as a result of 
+	  a <literal>:load</literal> or <literal>:module</literal> commands. </para>
 	</listitem>
       </varlistentry>
 
@@ -2587,6 +2598,18 @@ Prelude> :set -fno-glasgow-exts
           <para>See <xref linkend="ghci-windows"/>.</para>
         </listitem>
       </varlistentry>
+
+      <varlistentry>
+	<term>The default buffering mode is different in GHCi to GHC.</term>
+        <listitem>
+          <para>
+            In GHC, the stdout handle is line-buffered by default.
+            However, in GHCi we turn off the buffering on stdout,
+            because this is normally what you want in an interpreter:
+            output appears as it is generated.
+          </para>
+        </listitem>
+      </varlistentry>
     </variablelist>
   </sect1>