added InputParameter for an extra layer of abstraction that we can use to define custom handling of references. For example this is used in RcppArmadillo

Author: romainfrancois

ChangeLog

@@ -3,7 +3,11 @@
 	* src/api.cpp : added "long long" to the capabilities function. 
 	* include/Rcpp/platform/compiler.h : demangling is definitely available
 	on all mac versions using gcc. No point is testing for OSX version. 
-
+	* include/Rcpp/InputParameter.h : extra layer of abstraction to allow for
+	custom handling of references etc ... used in RcppArmadillo
+	* src/attributes.cpp : using InputParameter
+	* DESCRIPTION: bump to 0.10.4.4
+	
 2013-09-12 Romain Francois <romain@r-enthusiasts.com>
 
 	* include/Rcpp/platform/compiler.h : patch submitted by Murray for better

DESCRIPTION

@@ -1,6 +1,6 @@
 Package: Rcpp
 Title: Seamless R and C++ Integration
-Version: 0.10.4.3
+Version: 0.10.4.4
 Date: $Date$
 Author: Dirk Eddelbuettel and Romain Francois, with contributions 
  by Douglas Bates, John Chambers and JJ Allaire

inst/include/Rcpp/InputParameter.h

@@ -0,0 +1,40 @@
+// -*- mode: C++; c-indent-level: 4; c-basic-offset: 4; indent-tabs-mode: nil; -*-
+//
+// InputParameter.h: Rcpp R/C++ interface class library -- 
+//
+// Copyright (C) 2013    Dirk Eddelbuettel and Romain Francois
+//
+// This file is part of Rcpp.
+//
+// Rcpp is free software: you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 2 of the License, or
+// (at your option) any later version.
+//
+// Rcpp is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Rcpp.  If not, see <http://www.gnu.org/licenses/>.
+
+#ifndef Rcpp__InputParameter__h
+#define Rcpp__InputParameter__h
+
+namespace Rcpp {
+    
+    template <typename T>
+    class InputParameter {
+    public:
+        InputParameter(SEXP x_) : x(x_){}
+        
+        inline operator T() { return as<T>(x) ; }
+        
+    private:
+        SEXP x ;
+    } ;
+    
+}
+
+#endif

inst/include/RcppCommon.h

@@ -110,6 +110,7 @@ namespace Rcpp{
 #include <Rcpp/internal/export.h>
 #include <Rcpp/internal/r_coerce.h>
 #include <Rcpp/as.h>
+#include <Rcpp/InputParameter.h>
 #include <Rcpp/is.h>
 
 #include <Rcpp/vector/VectorBase.h>

src/attributes.cpp

@@ -2167,9 +2167,8 @@ namespace attributes {
             for (size_t i = 0; i<arguments.size(); i++) {
                 const Argument& argument = arguments[i];
 
-                ostr << "        " << argument.type().full_name() << " " << argument.name() 
-                     << " = " << "Rcpp::as<"  << argument.type().full_name() << " >(" 
-                     << argument.name() << "SEXP);" << std::endl;
+                ostr << "        Rcpp::InputParameter< " << argument.type().full_name() << "> " << argument.name() 
+                     << "(" << argument.name() << "SEXP );" << std::endl;
             }
 
             ostr << "        ";