From f22ade8ee4705abaa635fa482e97d0b80aa45912 Mon Sep 17 00:00:00 2001
From: Benoit Jacob <jacob.benoit.1@gmail.com>
Date: Fri, 23 Apr 2010 09:05:46 -0400
Subject: [PATCH] restrict operator[] to vectors, not matrices.

---
 Eigen/src/Core/Coeffs.h            | 4 ++++
 Eigen/src/Core/util/StaticAssert.h | 3 ++-
 test/basicstuff.cpp                | 8 ++++++++
 3 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/Eigen/src/Core/Coeffs.h b/Eigen/src/Core/Coeffs.h
index 727dea75e..d27a830dc 100644
--- a/Eigen/src/Core/Coeffs.h
+++ b/Eigen/src/Core/Coeffs.h
@@ -164,6 +164,8 @@ template<typename Derived>
 EIGEN_STRONG_INLINE const typename DenseBase<Derived>::CoeffReturnType DenseBase<Derived>
   ::operator[](int index) const
 {
+  EIGEN_STATIC_ASSERT(Derived::IsVectorAtCompileTime,
+                      THE_BRACKET_OPERATOR_IS_ONLY_FOR_VECTORS__USE_THE_PARENTHESIS_OPERATOR_INSTEAD)
   ei_assert(index >= 0 && index < size());
   return derived().coeff(index);
 }
@@ -217,6 +219,8 @@ template<typename Derived>
 EIGEN_STRONG_INLINE typename ei_traits<Derived>::Scalar& DenseBase<Derived>
   ::operator[](int index)
 {
+  EIGEN_STATIC_ASSERT(Derived::IsVectorAtCompileTime,
+                      THE_BRACKET_OPERATOR_IS_ONLY_FOR_VECTORS__USE_THE_PARENTHESIS_OPERATOR_INSTEAD)
   ei_assert(index >= 0 && index < size());
   return derived().coeffRef(index);
 }
diff --git a/Eigen/src/Core/util/StaticAssert.h b/Eigen/src/Core/util/StaticAssert.h
index b9f31d3e8..31f7d0038 100644
--- a/Eigen/src/Core/util/StaticAssert.h
+++ b/Eigen/src/Core/util/StaticAssert.h
@@ -83,7 +83,8 @@
         THE_MATRIX_OR_EXPRESSION_THAT_YOU_PASSED_DOES_NOT_HAVE_THE_EXPECTED_TYPE,
         THIS_METHOD_IS_ONLY_FOR_EXPRESSIONS_WITH_DIRECT_MEMORY_ACCESS_SUCH_AS_MAP_OR_PLAIN_MATRICES,
         YOU_ALREADY_SPECIFIED_THIS_STRIDE,
-        INVALID_STORAGE_ORDER_FOR_THIS_VECTOR_EXPRESSION
+        INVALID_STORAGE_ORDER_FOR_THIS_VECTOR_EXPRESSION,
+        THE_BRACKET_OPERATOR_IS_ONLY_FOR_VECTORS__USE_THE_PARENTHESIS_OPERATOR_INSTEAD
       };
     };
 
diff --git a/test/basicstuff.cpp b/test/basicstuff.cpp
index 70b65a7be..efc08655d 100644
--- a/test/basicstuff.cpp
+++ b/test/basicstuff.cpp
@@ -22,6 +22,8 @@
 // License and a copy of the GNU General Public License along with
 // Eigen. If not, see <http://www.gnu.org/licenses/>.
 
+#define EIGEN_NO_STATIC_ASSERT
+
 #include "main.h"
 
 template<typename MatrixType> void basicStuff(const MatrixType& m)
@@ -96,6 +98,12 @@ template<typename MatrixType> void basicStuff(const MatrixType& m)
     VERIFY_RAISES_ASSERT(m1 = (m2.block(0,0, rows-1, cols-1)));
   }
 
+  if(cols!=1 && rows!=1)
+  {
+    VERIFY_RAISES_ASSERT(m1[0]);
+    VERIFY_RAISES_ASSERT((m1+m1)[0]);
+  }
+
   VERIFY_IS_APPROX(m3 = m1,m1);
   MatrixType m4;
   VERIFY_IS_APPROX(m4 = m1,m1);