:force is not unsupported anymore

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

diff --git a/docs/users_guide/ghci.xml b/docs/users_guide/ghci.xml
index 06eb348..aaa9c46 100644 (file)
--- a/docs/users_guide/ghci.xml
+++ b/docs/users_guide/ghci.xml
@@ -1244,9 +1244,9 @@ li - (_t1::[Maybe Integer])
 Prelude> head li
 Just 1
 Prelude> :sp li
-li - [Just 1 | _]
+li - Just 1 : _
 Prelude> :p li
-li - [Just 1 | (_t2::[Maybe Integer])]
+li - Just 1 : (_t2::[Maybe Integer])
 Prelude> last li
 Just 5
 Prelude> :sp li
@@ -1262,8 +1262,6 @@ li - [Just 1,(_t6::Maybe Integer),Just 3,(_t7::Maybe Integer),Just 4]
         to help us observe how the <literal>li</literal> variable is evaluated progressively as we operate
          with it. Note for instance how <quote>last</quote> traverses all the elements of
         the list to compute its result, but without evaluating the individual elements.</para>
-           <para>Finally note that the Prolog convention of [head | tail] is used by 
-        <literal>:sprint</literal> to display unevaluated lists.
          </para>
        </listitem>
       </varlistentry>
@@ -1389,7 +1387,7 @@ li - _
 Prelude> head li
 Just 1
 Prelude> :sp li
-li - [Just 1 | _]
+li - Just 1 : _
 Prelude> last li
 Just 5
 Prelude> :sp li
@@ -1398,8 +1396,6 @@ li - [Just 1,_,_,_,Just 5]
          The example uses <literal>:sprint</literal> to help us observe how the <literal>li</literal> variable is evaluated progressively as we operate
          with it. Note for instance how <quote>last</quote> traverses all the elements of
         the list to compute its result, but without evaluating the individual elements.</para>
-           <para>Finally note that the Prolog convention of [head | tail] is used by 
-        <literal>:sprint</literal> to display unevaluated lists.
          </para>
        </listitem>
       </varlistentry>
@@ -1880,7 +1876,7 @@ Main.hs:15> x'
           Note that a wrong coercion will likely result in your debugging session being interrupted by a segmentation fault 
          </para></listitem>
        </varlistentry>
-       <varlistentry> <term> * The undocumented (and unsupported) &colon;force command </term>
+       <varlistentry> <term> * The <literal>:force</literal> command </term>
          <listitem><para> 
              equivalent to <literal> :print</literal> with automatic 
              <literal>seq</literal> forcing, 
@@ -1952,6 +1948,32 @@ Main.hs:15> x'
 
   </sect1>
 
+  <sect1 id="ghci-obj">
+    <title>Compiling to object code inside GHCi</title>
+
+    <para>By default, GHCi compiles Haskell source code into byte-code
+    that is interpreted by the runtime system.  GHCi can also compile
+    Haskell code to object code: to turn on this feature, use the
+    <option>-fobject-code</option> flag either on the command line or
+    with <literal>:set</literal> (the option
+    <option>-fbyte-code</option> restores byte-code compilation
+    again).  Compiling to object code takes longer, but typically the
+    code will execute 10-20 times faster than byte-code.</para>
+
+    <para>Compiling to object code inside GHCi is particularly useful
+    if you are developing a compiled application, because the
+    <literal>:reload</literal> command typically runs much faster than
+    restarting GHC with <option>--make</option> from the command-line,
+    because all the interface files are already cached in
+    memory.</para>
+
+    <para>There are disadvantages to compiling to object-code: you
+    can't set breakpoints in object-code modules, for example.  Only
+    the exports of an object-code module will be visible in GHCi,
+    rather than all top-level bindings as in interpreted
+    modules.</para>
+  </sect1>
+
   <sect1 id="ghci-faq">
     <title>FAQ and Things To Watch Out For</title>