From 613737b1e6b7f6660536b8c8d959639cb386f5cf Mon Sep 17 00:00:00 2001
From: "simonpj@microsoft.com" <unknown>
Date: Wed, 2 May 2007 10:38:15 +0000
Subject: [PATCH] Document the fact that you can't make a newtype of an
 unboxed data type

---
 docs/users_guide/glasgow_exts.xml |    7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/docs/users_guide/glasgow_exts.xml b/docs/users_guide/glasgow_exts.xml
index 4ed8c2a..61cff6e 100644
--- a/docs/users_guide/glasgow_exts.xml
+++ b/docs/users_guide/glasgow_exts.xml
@@ -381,6 +381,13 @@ worse, the unboxed value might be larger than a pointer
 (<literal>Double&num;</literal> for instance).
 </para>
 </listitem>
+<listitem><para> You cannot define a newtype whose representation type
+(the argument type of the data constructor) is an unboxed type.  Thus,
+this is illegal:
+<programlisting>
+  newtype A = MkA Int#
+</programlisting>
+</para></listitem>
 <listitem><para> You cannot bind a variable with an unboxed type
 in a <emphasis>top-level</emphasis> binding.
 </para></listitem>
-- 
1.7.10.4