3 files changed, 58 insertions, 26 deletions
diff --git a/Eigen/src/Core/ArithmeticSequence.h b/Eigen/src/Core/ArithmeticSequence.h
index 941028893..db6da0001 100644
--- a/Eigen/src/Core/ArithmeticSequence.h
+++ b/Eigen/src/Core/ArithmeticSequence.h
@@ -329,9 +329,9 @@ seq(const symbolic::BaseExpr<FirstTypeDerived> &f, const symbolic::BaseExpr<Last
   * \sa lastN(SizeType), seqN(FirstType,SizeType), seq(FirstType,LastType,IncrType) */
 template<typename SizeType,typename IncrType>
 auto lastN(SizeType size, IncrType incr)
--> decltype(seqN(Eigen::placeholders::last-(size-fix<1>())*incr, size, incr))
+-> decltype(seqN(Eigen::last-(size-fix<1>())*incr, size, incr))
 {
-  return seqN(Eigen::placeholders::last-(size-fix<1>())*incr, size, incr);
+  return seqN(Eigen::last-(size-fix<1>())*incr, size, incr);
 }
 
 /** \cpp11
@@ -342,9 +342,9 @@ auto lastN(SizeType size, IncrType incr)
   * \sa lastN(SizeType,IncrType, seqN(FirstType,SizeType), seq(FirstType,LastType) */
 template<typename SizeType>
 auto lastN(SizeType size)
--> decltype(seqN(Eigen::placeholders::last+fix<1>()-size, size))
+-> decltype(seqN(Eigen::last+fix<1>()-size, size))
 {
-  return seqN(Eigen::placeholders::last+fix<1>()-size, size);
+  return seqN(Eigen::last+fix<1>()-size, size);
 }
 #endif
 
@@ -375,6 +375,39 @@ struct get_compile_time_incr<ArithmeticSequence<FirstType,SizeType,IncrType> > {
 
 } // end namespace internal
 
+/** \namespace Eigen::indexing
+  * \ingroup Core_Module
+  * 
+  * The sole purpose of this namespace is to be able to import all functions
+  * and symbols that are expected to be used within operator() for indexing
+  * and slicing. If you already imported the whole Eigen namespace:
+  * \code using namespace Eigen; \endcode
+  * then you are already all set. Otherwise, if you don't want/cannot import
+  * the whole Eigen namespace, the following line:
+  * \code using namespace Eigen::indexing; \endcode
+  * is equivalent to:
+  * \code
+  using Eigen::all;
+  using Eigen::seq;
+  using Eigen::seqN;
+  using Eigen::lastN; // c++11 only
+  using Eigen::last;
+  using Eigen::lastp1;
+  using Eigen::fix;
+  \endcode
+  */
+namespace indexing {
+  using Eigen::all;
+  using Eigen::seq;
+  using Eigen::seqN;
+  #if EIGEN_HAS_CXX11
+  using Eigen::lastN;
+  #endif
+  using Eigen::last;
+  using Eigen::lastp1;
+  using Eigen::fix;
+}
+
 } // end namespace Eigen
 
 #endif // EIGEN_ARITHMETIC_SEQUENCE_H
diff --git a/Eigen/src/Core/util/IndexedViewHelper.h b/Eigen/src/Core/util/IndexedViewHelper.h
index 5d7cf8e91..40e16fdb4 100644
--- a/Eigen/src/Core/util/IndexedViewHelper.h
+++ b/Eigen/src/Core/util/IndexedViewHelper.h
@@ -13,13 +13,6 @@
 
 namespace Eigen {
 
-/** \namespace Eigen::placeholders
-  * \ingroup Core_Module
-  *
-  * Namespace containing symbolic placeholder and identifiers
-  */
-namespace placeholders {
-
 namespace internal {
 struct symbolic_last_tag {};
 }
@@ -35,36 +28,35 @@ struct symbolic_last_tag {};
   * A typical usage example would be:
   * \code
   * using namespace Eigen;
-  * using Eigen::placeholders::last;
+  * using Eigen::last;
   * VectorXd v(n);
   * v(seq(2,last-2)).setOnes();
   * \endcode
   *
   * \sa end
   */
-static const symbolic::SymbolExpr<internal::symbolic_last_tag> last;
+static const symbolic::SymbolExpr<internal::symbolic_last_tag> last; // PLEASE use Eigen::last   instead of Eigen::placeholders::last
 
-/** \var end
+/** \var lastp1
   * \ingroup Core_Module
   *
-  * Can be used as a parameter to Eigen::seq and Eigen::seqN functions to symbolically reference the last+1 element/row/columns
-  * of the underlying vector or matrix once passed to DenseBase::operator()(const RowIndices&, const ColIndices&).
+  * Can be used as a parameter to Eigen::seq and Eigen::seqN functions to symbolically
+  * reference the last+1 element/row/columns of the underlying vector or matrix once
+  * passed to DenseBase::operator()(const RowIndices&, const ColIndices&).
   *
   * This symbolic placeholder support standard arithmetic operation.
-  * It is essentially an alias to last+1
+  * It is essentially an alias to last+fix<1>.
   *
   * \sa last
   */
 #ifdef EIGEN_PARSED_BY_DOXYGEN
-static const auto end = last+1;
+static const auto lastp1 = last+fix<1>;
 #else
 // Using a FixedExpr<1> expression is important here to make sure the compiler
 // can fully optimize the computation starting indices with zero overhead.
-static const symbolic::AddExpr<symbolic::SymbolExpr<internal::symbolic_last_tag>,symbolic::ValueExpr<Eigen::internal::FixedInt<1> > > end(last+fix<1>());
+static const symbolic::AddExpr<symbolic::SymbolExpr<internal::symbolic_last_tag>,symbolic::ValueExpr<Eigen::internal::FixedInt<1> > > lastp1(last+fix<1>());
 #endif
 
-} // end namespace placeholders
-
 namespace internal {
 
  // Replace symbolic last/end "keywords" by their true runtime value
@@ -76,7 +68,7 @@ FixedInt<N> eval_expr_given_size(FixedInt<N> x, Index /*size*/)   { return x; }
 template<typename Derived>
 Index eval_expr_given_size(const symbolic::BaseExpr<Derived> &x, Index size)
 {
-  return x.derived().eval(placeholders::last=size-1);
+  return x.derived().eval(last=size-1);
 }
 
 // Extract increment/step at compile time
@@ -172,14 +164,21 @@ template<int Size> struct get_compile_time_incr<AllRange<Size> > {
 } // end namespace internal
 
 
-namespace placeholders {
-
 /** \var all
   * \ingroup Core_Module
   * Can be used as a parameter to DenseBase::operator()(const RowIndices&, const ColIndices&) to index all rows or columns
   */
-static const Eigen::internal::all_t all;
+static const Eigen::internal::all_t all; // PLEASE use Eigen::all instead of Eigen::placeholders::all
+
+
+namespace placeholders {
+  typedef symbolic::SymbolExpr<internal::symbolic_last_tag> last_t;
+  typedef symbolic::AddExpr<symbolic::SymbolExpr<internal::symbolic_last_tag>,symbolic::ValueExpr<Eigen::internal::FixedInt<1> > > end_t;
+  typedef Eigen::internal::all_t all_t;
 
+  EIGEN_DEPRECATED static const all_t  all  = Eigen::all;    // PLEASE use Eigen::all    instead of Eigen::placeholders::all
+  EIGEN_DEPRECATED static const last_t last = Eigen::last;   // PLEASE use Eigen::last   instead of Eigen::placeholders::last
+  EIGEN_DEPRECATED static const end_t  end  = Eigen::lastp1; // PLEASE use Eigen::lastp1 instead of Eigen::placeholders::end
 }
 
 } // end namespace Eigen
diff --git a/Eigen/src/Core/util/SymbolicIndex.h b/Eigen/src/Core/util/SymbolicIndex.h
index 41d477056..17cf46f05 100644
--- a/Eigen/src/Core/util/SymbolicIndex.h
+++ b/Eigen/src/Core/util/SymbolicIndex.h
@@ -35,7 +35,7 @@ namespace Eigen {
   * std::cout << expr98.eval(x=6) << "\n";
   * \endcode
   *
-  * It is currently only used internally to define and manipulate the placeholders::last and placeholders::end symbols in Eigen::seq and Eigen::seqN.
+  * It is currently only used internally to define and manipulate the Eigen::last and Eigen::lastp1 symbols in Eigen::seq and Eigen::seqN.
   *
   */
 namespace symbolic {