+ creating a branch for a xpressive extension that allows nesting

of regular expressions


[SVN r38759]

include/boost/detail/identifier.hpp

@@ -0,0 +1,89 @@
+//  boost/identifier.hpp  ----------------------------------------------------//
+
+//  Copyright Beman Dawes 2006
+
+//  Distributed under the Boost Software License, Version 1.0. (See accompanying
+//  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+
+//  See documentation at http://www.boost.org/libs/utility
+
+#ifndef BOOST_IDENTIFIER_HPP
+#define BOOST_IDENTIFIER_HPP
+
+#include <boost/utility/enable_if.hpp>
+#include <boost/type_traits/is_base_of.hpp>
+#include <iosfwd>
+
+namespace boost
+{
+  namespace detail
+  {
+    //  class template identifier  ---------------------------------------------//
+
+    //  Always used as a base class so that different instantiations result in
+    //  different class types even if instantiated with the same value type T.
+
+    //  Expected usage is that T is often an integer type, best passed by
+    //  value. There is no reason why T can't be a possibly larger class such as
+    //  std::string, best passed by const reference.
+
+    //  This implementation uses pass by value, based on expected common uses.
+
+    template <typename T, typename D>
+    class identifier
+    {
+    public:
+      typedef T value_type;
+
+      const value_type value() const           { return m_value; }
+      void  assign( value_type v )             { m_value = v; }
+
+      bool operator==( const D & rhs ) const   { return m_value == rhs.m_value; }
+      bool operator!=( const D & rhs ) const   { return m_value != rhs.m_value; }
+      bool operator< ( const D & rhs ) const   { return m_value <  rhs.m_value; }
+      bool operator<=( const D & rhs ) const   { return m_value <= rhs.m_value; }
+      bool operator> ( const D & rhs ) const   { return m_value >  rhs.m_value; }
+      bool operator>=( const D & rhs ) const   { return m_value >= rhs.m_value; }
+
+      typedef void (*unspecified_bool_type)(D); // without the D, unspecified_bool_type 
+      static void unspecified_bool_true(D){}    // conversion allows relational operators
+                                                // between different identifier types
+
+      operator unspecified_bool_type() const   { return m_value == value_type() ? 0 : unspecified_bool_true; }
+      bool operator!() const                   { return m_value == value_type(); }
+
+    // constructors are protected so that class can only be used as a base class
+    protected:
+      identifier()                             {}
+      explicit identifier( value_type v )      : m_value(v) {}
+
+  #if !defined(BOOST_MSVC) || BOOST_MSVC > 1300  // 1300 == VC++ 7.0 bug workaround
+    private:
+  #endif
+      T m_value;
+    };
+
+  //#ifndef BOOST_NO_SFINAE
+
+  //  template <class Ostream, class Id>
+  //    typename enable_if< is_base_of< identifier< typename Id::value_type, Id >, Id >, 
+  //      Ostream & >::type operator<<( Ostream & os, const Id & id )
+  //  {
+  //    return os << id.value();
+  //  }
+
+  //  template <class Istream, class Id>
+  //    typename enable_if< is_base_of< identifier< typename Id::value_type, Id >, Id >, 
+  //      Istream & >::type operator>>( Istream & is, Id & id )
+  //  {
+  //    typename Id::value_type v;
+  //    is >> v;
+  //    id.value( v );
+  //    return is;
+  //  }
+  //#endif
+
+  } // namespace detail
+} // namespace boost
+
+#endif // BOOST_IDENTIFIER_HPP

include/boost/detail/indirect_traits.hpp

@@ -398,7 +398,7 @@ struct reference_to_pointer_impl
     
     typedef mpl::bool_<value> type;
 };
-   
+    
 template <class T>
 struct is_reference_to_pointer
   : mpl::eval_if<is_reference<T>, reference_to_pointer_impl<T>, mpl::false_>::type

include/boost/pending/ct_if.hpp

@@ -3,107 +3,39 @@
 // accompanying file LICENSE_1_0.txt or copy at
 // http://www.boost.org/LICENSE_1_0.txt)
 
-// The ct_if implementation that avoids partial specialization is
-// based on the IF class by Ulrich W. Eisenecker and Krzysztof
-// Czarnecki.
+// This header replaces the implementation of ct_if that preceded the
+// introduction of Boost.MPL with a facade that defers to that reviewed and
+// accepted library.
+
+// Author: Ronald Garcia
+// Date: 20 October, 2006
+
 
 #ifndef BOOST_CT_IF_HPP
 #define BOOST_CT_IF_HPP
 
-#include <boost/config.hpp>
 
-/*
-  There is a bug in the Borland compiler with regards to using
-  integers to specialize templates. This made it hard to use ct_if in
-  the graph library. Changing from 'ct_if' to 'ct_if_t' fixed the
-  problem.
-*/
+// A stub implementation in terms of Boost.MPL
 
-#include <boost/type_traits/integral_constant.hpp> // true_type and false_type
+#include <boost/mpl/if.hpp>
+#include <boost/mpl/not.hpp>
+#include <boost/mpl/and.hpp>
+// true_type and false_type are used by applications of ct_if
+#include <boost/type_traits/integral_constant.hpp> 
 
 namespace boost {
 
-  struct ct_if_error { };
-
   template <class A, class B>
-  struct ct_and { typedef false_type type; };
-  template <> struct ct_and<true_type,true_type> { typedef true_type type; };
+  struct ct_and : boost::mpl::and_<A,B> {};
 
-  template <class A> struct ct_not { typedef ct_if_error type; };
-  template <> struct ct_not<true_type> { typedef false_type type; };
-  template <> struct ct_not<false_type> { typedef true_type type; };
+  template <class A>
+  struct ct_not : mpl::not_<A> {};
 
-#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
-
-// agurt, 15/sep/02: in certain cases Borland has problems with
-// choosing the right 'ct_if' specialization even though 'cond' 
-// _does_ equal '1'; the easiest way to fix it is to make first 
-// 'ct_if' non-type template parameter boolean.
-#if !defined(__BORLANDC__)
   template <bool cond, class A, class B>
-  struct ct_if { typedef ct_if_error type; };
-  template <class A, class B>
-  struct ct_if<true, A, B> { typedef A type; };
-  template <class A, class B>
-  struct ct_if<false, A, B> { typedef B type; };
-#else
-  template <bool cond, class A, class B>
-  struct ct_if { typedef A type; };
-  template <class A, class B>
-  struct ct_if<false, A, B> { typedef B type; };
-#endif
+  struct ct_if : mpl::if_c<cond,A,B> {};
 
   template <class cond, class A, class B>
-  struct ct_if_t { typedef ct_if_error type; };
-  template <class A, class B>
-  struct ct_if_t<true_type, A, B> { typedef A type; };
-  template <class A, class B>
-  struct ct_if_t<false_type, A, B> { typedef B type; };
-
-#else
-
-  namespace detail {
-
-    template <int condition, class A, class B> struct IF;
-    template <int condition> struct SlectSelector;
-    struct SelectFirstType;
-    struct SelectSecondType;
-    
-    struct SelectFirstType {
-      template<class A, class B>
-      struct Template {        typedef A type; };
-    };
-    
-    struct SelectSecondType {
-      template<class A, class B>
-      struct Template { typedef B type; };
-    };
-    
-    template<int condition>
-    struct SlectSelector {
-      typedef SelectFirstType type;
-    };
-    
-    template <>
-    struct SlectSelector<0> {
-      typedef SelectSecondType type;
-    };
-
-  } // namespace detail
-    
-  template<int condition, class A, class B>
-  struct ct_if
-  {
-    typedef typename detail::SlectSelector<condition>::type Selector;
-    typedef typename Selector::template Template<A, B>::type type;
-  };
-  
-  template <class cond, class A, class B>
-  struct ct_if_t { 
-    typedef typename ct_if<cond::value, A, B>::type type;
-  };
-
-#endif
+  struct ct_if_t : mpl::if_<cond,A,B> {};
 
 } // namespace boost
 

include/boost/pending/integer_log2.hpp

@@ -12,14 +12,17 @@
 //          http://www.boost.org/LICENSE_1_0.txt)
 //
 // ------------------------------------------------------
-
+//
+// $Id$
 
 
 #ifndef BOOST_INTEGER_LOG2_HPP_GP_20030301
 #define BOOST_INTEGER_LOG2_HPP_GP_20030301
 
-#include <cassert>
-#include <climits> // actually used for Borland only
+#include <assert.h>
+#ifdef __BORLANDC__
+#include <climits>
+#endif
 #include "boost/limits.hpp"
 #include "boost/config.hpp"