Use iformat and Input_rep<double> instead of an additional function

Stream_support/benchmark/Stream_support/read_doubles.cpp

@@ -6,6 +6,7 @@
 #include <fstream>
 #include <string>
 #include <CGAL/Timer.h>
+#include <CGAL/IO/io.h>
 #include <boost/lexical_cast.hpp>
 
 
@@ -27,7 +28,7 @@ int main(int argc, char* argv[])
     std::cerr << "operator"<< std::endl;
     t.start();
     for(int i=0; i<n; i++){
-      CGAL::extract(std::cin, d);
+      std::cin >> d;
       sum+= d;
     }
     t.stop();
@@ -67,6 +68,16 @@ int main(int argc, char* argv[])
       sum+= d;
     }
     t.stop();
+  } 
+
+  if(choice == 4){
+    std::cerr << "iformat"<< std::endl;
+    t.start();
+    for(int i=0; i<n; i++){
+      std::cin >> CGAL::iformat(d);
+      sum+= d;
+    }
+    t.stop();
   }
   std::cerr.precision(17);
   std::cerr << "sum = " << sum << std::endl;

Stream_support/include/CGAL/IO/io.h

@@ -91,6 +91,25 @@ public:
     std::istream& operator()( std::istream& in) const { return (in >> t); }
 };
 
+
+#if defined( _MSC_VER ) && ( _MSC_VER > 1600 ) && (! defined( CGAL_NO_IFORMAT_DOUBLE ))
+template <>
+class Input_rep<double> {
+    double& t;
+public:
+    //! initialize with a reference to \a t.
+    Input_rep( double& tt) : t(tt) {}
+    //! perform the input, calls \c operator\>\> by default.
+    std::istream& operator()( std::istream& is) const 
+  {  
+    std::string s;
+    is >> s;
+    sscanf(s.c_str(), "%lf", &t);
+    return is; 
+  }
+};
+#endif
+
 /*! \relates Input_rep
     \brief stream input to the \c Input_rep calls its \c operator().
 */
@@ -168,28 +187,6 @@ bool
 is_binary(std::ios& i);
 
 
-#ifdef CGAL_GENERIC_EXTRACT
-  template <typename T>
-  inline std::istream& extract(std::istream& is, T &t)
-  {
-    is >> t;
-    return is;
-  }
-
-  template <>
-#endif
-
-  inline std::istream& extract(std::istream& is, double &d)
-{
-#if defined( _MSC_VER ) && ( _MSC_VER > 1600 )
-  std::string s;
-  is >> s;
-  sscanf(s.c_str(), "%lf", &d);
-#else
-  is >> d;
-#endif
-  return is;
-}
 
 template < class T >
 inline