[project @ 2001-08-24 11:39:49 by simonmar]

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

diff --git a/ghc/docs/users_guide/ghci.sgml b/ghc/docs/users_guide/ghci.sgml
index 23c4e70..6c65538 100644 (file)
--- a/ghc/docs/users_guide/ghci.sgml
+++ b/ghc/docs/users_guide/ghci.sgml
@@ -12,7 +12,7 @@
   you're famililar with Hugs<indexterm><primary>Hugs</primary>
   </indexterm>, then you'll be right at home with GHCi.  However, GHCi
   also has support for interactively loading compiled code, as well as
-  supporting all<footnote><para>except the FFI, at the moment</para>
+  supporting all<footnote><para>except <literal>foreign export</literal>, at the moment</para>
   </footnote>the language extensions that GHC provides.</para>
   <indexterm><primary>FFI</primary><secondary>GHCi support</secondary></indexterm>
   <indexterm><primary>Foreign Function Interface</primary><secondary>GHCi support</secondary></indexterm>
@@ -150,6 +150,16 @@ Main> fac 17
       in the same directory and you can't call them all
       <filename>Main.hs</filename>.</para>
 
+      <para>One consequence of the way that GHCi follows dependencies
+      to find modules to load is that every module must have a source
+      file.  The only exception to the rule is modules that come from
+      a package, including the <literal>Prelude</literal> and standard
+      libraries such as <literal>IO</literal> and
+      <literal>Complex</literal>.  If you attempt to load a module for
+      which GHCi can't find a source file, even if there are object
+      and interface files for the module, you'll get an error
+      message.</para>
+
       <para>One final note: if you load a module called Main, it must
       contain a <literal>main</literal> function, just like in
       GHC.</para>
@@ -724,6 +734,24 @@ Prelude> :def make (\_ -> return ":! ghc --make Main")
       </varlistentry>
 
       <varlistentry>
+       <term><literal>:info</literal> <replaceable>name</replaceable>
+       ...</term>
+       <indexterm><primary><literal>:info</literal></primary>
+       </indexterm>
+       <listitem>
+         <para>Displays information about the given name(s).  For
+         example, if <replaceable>name</replaceable> is a class, then
+         the class methods and their types will be printed;  if
+         <replaceable>name</replaceable> is a type constructor, then
+         its definition will be printed;  if
+         <replaceable>name</replaceable> is a function, then its type
+         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>
+       </listitem>
+      </varlistentry>
+
+      <varlistentry>
        <term><literal>:load</literal>
        <replaceable>module</replaceable> ...</term>
        <indexterm><primary><literal>:load</literal></primary></indexterm>
@@ -947,7 +975,7 @@ Prelude> :set -fno-glasgow-exts
     </sect2>
   </sect1>
 
-  <sect1>
+  <sect1 id="ghci-dot-files">
     <title>The <filename>.ghci</filename> file</title>
     <indexterm><primary><filename>.ghci</filename></primary><secondary>file</secondary>
     </indexterm>
@@ -977,6 +1005,34 @@ Prelude> :set -fno-glasgow-exts
     a static one, but in fact it works to set it using
     <literal>:set</literal> like this.  The changes won't take effect
     until the next <literal>:load</literal>, though.)</para>
+
+    <para>Two command-line options control whether the
+    <filename>.ghci</filename> files are read:</para>
+
+    <variablelist>
+      <varlistentry>
+       <term><option>-ignore-dot-ghci</option></term>
+       <indexterm><primary><option>-ignore-dot-ghci</option></primary>
+       </indexterm>
+       <listitem>
+         <para>Don't read either <filename>./.ghci</filename> or
+         <filename>$HOME/.ghci</filename> when starting up.</para>
+       </listitem>
+      </varlistentry>
+      <varlistentry>
+       <term><option>-read-dot-ghci</option></term>
+       <indexterm><primary><option>-read-dot-ghci</option></primary>
+       </indexterm>
+       <listitem>
+         <para>Read <filename>.ghci</filename> and
+         <filename>$HOME/.ghci</filename>.  This is normally the
+         default, but the <option>-read-dot-ghci</option> option may
+         be used to override a previous
+         <option>-ignore-dot-ghci</option> option.</para>
+       </listitem>
+      </varlistentry>
+    </variablelist>
+
   </sect1>
 
   <sect1>
@@ -1000,15 +1056,6 @@ Prelude> :set -fno-glasgow-exts
       </varlistentry>
 
       <varlistentry>
-       <term><literal>System.exit</literal> causes GHCi to exit!</term>
-       <indexterm><primary><literal>System.exit</literal></primary><secondary>in
-       GHCi</secondary></indexterm>
-       <listitem>
-         <para>Yes, it does.</para>
-       </listitem>
-      </varlistentry>
-
-      <varlistentry>
        <term><literal>System.getArgs</literal> returns GHCi's command
        line arguments!</term>
        <listitem>
@@ -1017,7 +1064,7 @@ Prelude> :set -fno-glasgow-exts
       </varlistentry>
 
       <varlistentry>
-       <term>The interpreter can't load modules with FFI
+       <term>The interpreter can't load modules with foreign export
        declarations!</term>
        <listitem>
          <para>Unfortunately not.  We haven't implemented it yet.