[project @ 2005-05-05 07:43:28 by simonpj]

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

diff --git a/ghc/docs/users_guide/glasgow_exts.xml b/ghc/docs/users_guide/glasgow_exts.xml
index aecfcbc..2df223b 100644 (file)
--- a/ghc/docs/users_guide/glasgow_exts.xml
+++ b/ghc/docs/users_guide/glasgow_exts.xml
@@ -4331,7 +4331,7 @@ Assertion failures can be caught, see the documentation for the
        </listitem>
 
        <listitem>
-         <para>You can deprecate a function, class, or type, with the
+         <para>You can deprecate a function, class, type, or data constructor, with the
          following top-level declaration:</para>
 <programlisting>
    {-# DEPRECATED f, C, T "Don't use these" #-}
@@ -4339,6 +4339,13 @@ Assertion failures can be caught, see the documentation for the
          <para>When you compile any module that imports and uses any
           of the specified entities, GHC will print the specified
           message.</para>
+         <para> You can only depecate entities declared at top level in the module
+         being compiled, and you can only use unqualified names in the list of
+         entities being deprecated.  A capitalised name, such as <literal>T</literal>
+         refers to <emphasis>either</emphasis> the type constructor <literal>T</literal>
+         <emphasis>or</emphasis> the data constructor <literal>T</literal>, or both if
+         both are in scope.  If both are in scope, there is currently no way to deprecate 
+         one without the other (c.f. fixities <xref linkend="infix-tycons"/>).</para>
        </listitem>
       </itemizedlist>
       Any use of the deprecated item, or of anything from a deprecated