Initial base_from_member commit

[SVN r11086]

include/boost/utility.hpp

@@ -10,23 +10,15 @@
 
 //  Classes appear in alphabetical order
 
-//  Revision History
-//  21 May 01  checked_delete() and checked_array_delete() added (Beman Dawes,
-//             suggested by Dave Abrahams, generalizing idea from Vladimir Prus)
-//  21 May 01  made next() and prior() inline (Beman Dawes)  
-//  26 Jan 00  protected noncopyable destructor added (Miki Jovanovic)
-//  10 Dec 99  next() and prior() templates added (Dave Abrahams)
-//  30 Aug 99  moved cast templates to cast.hpp (Beman Dawes)
-//   3 Aug 99  cast templates added
-//  20 Jul 99  name changed to utility.hpp 
-//   9 Jun 99  protected noncopyable default ctor
-//   2 Jun 99  Initial Version. Class noncopyable only contents (Dave Abrahams)
-
 #ifndef BOOST_UTILITY_HPP
 #define BOOST_UTILITY_HPP
 
-#include <boost/config.hpp>        // broken compiler workarounds 
-#include <boost/static_assert.hpp> 
+#include <boost/config.hpp>        // broken compiler workarounds
+#include <boost/static_assert.hpp>
+
+// certain headers are part of the <utility.hpp> interface
+#include <boost/utility/base_from_member.hpp>  
+ 
 #include <cstddef>                 // for size_t
 #include <utility>                 // for std::pair
 

include/boost/utility/base_from_member.hpp

@@ -0,0 +1,59 @@
+//  boost utility/base_from_member.hpp header file  --------------------------//
+
+//  (C) Copyright Daryle Walker 2001.  Permission to copy, use, modify, sell
+//  and distribute this software is granted provided this copyright
+//  notice appears in all copies.  This software is provided "as is" without
+//  express or implied warranty, and with no claim as to its suitability for
+//  any purpose.
+
+//  See http://www.boost.org for most recent version including documentation.
+
+#ifndef BOOST_UTILITY_BASE_FROM_MEMBER_HPP
+#define BOOST_UTILITY_BASE_FROM_MEMBER_HPP
+
+#include <boost/utility_fwd.hpp>  // self include
+
+
+namespace boost
+{
+
+//  Base-from-member class template  -----------------------------------------//
+
+// Helper to initialize a base object so a derived class can use this
+// object in the initialization of another base class.  Used by
+// Dietmar Kuehl from ideas by Ron Klatcho to solve the problem of a
+// base class needing to be initialized by a member.
+
+// Contributed by Daryle Walker
+
+template < typename MemberType, int UniqueID >
+class base_from_member
+{
+protected:
+    MemberType  member;
+
+    explicit  base_from_member()
+        : member()
+        {}
+
+    template< typename T1 >
+    explicit base_from_member( T1 x1 )
+        : member( x1 )
+        {}
+
+    template< typename T1, typename T2 >
+    explicit  base_from_member( T1 x1, T2 x2 )
+        : member( x1, x2 )
+        {}
+
+    template< typename T1, typename T2, typename T3 >
+    explicit  base_from_member( T1 x1, T2 x2, T3 x3 )
+        : member( x1, x2, x3 ) 
+        {}
+
+};  // boost::base_from_member
+
+}  // namespace boost
+
+
+#endif  // BOOST_UTILITY_BASE_FROM_MEMBER_HPP

include/boost/utility_fwd.hpp

@@ -0,0 +1,38 @@
+//  Boost utility_fwd.hpp header file  ---------------------------------------//
+
+//  (C) Copyright boost.org 2001.  Permission to copy, use, modify, sell
+//  and distribute this software is granted provided this copyright
+//  notice appears in all copies.  This software is provided "as is" without
+//  express or implied warranty, and with no claim as to its suitability for
+//  any purpose.
+
+//  See http://www.boost.org for most recent version including documentation.
+
+#ifndef BOOST_UTILITY_FWD_HPP
+#define BOOST_UTILITY_FWD_HPP
+
+
+namespace boost
+{
+
+
+//  From <boost/utility/base_from_member.hpp>  -------------------------------//
+
+template < typename MemberType, int UniqueID = 0 >
+    class base_from_member;
+
+
+//  From <boost/utility.hpp>  ------------------------------------------------//
+
+class noncopyable;
+
+template < class A, class B >
+    class tied;
+
+// Also has a few function templates
+
+
+}  // namespace boost
+
+
+#endif  // BOOST_UTILITY_FWD_HPP