Now algorithm::helpers::rtype is safer (due to ctype decay)

Author: Daniel C. Dillon

inst/include/Rcpp/algorithm.h

@@ -8,45 +8,6 @@ namespace Rcpp {
 namespace algorithm {
 
 namespace helpers {
-    template< typename T >
-    struct rtype_helper {
-        /*
-	typedef T type;
-        static RCPP_CONSTEXPR int RTYPE = REALSXP;
-        static inline double NA() { return NA_REAL; }
-        static inline RCPP_CONSTEXPR double ZERO() { return 0.0; }
-        static inline RCPP_CONSTEXPR double ONE() { return 1.0; }
-        */
-    };
-
-    template<>
-    struct rtype_helper< double > {
-        typedef double type;
-        static RCPP_CONSTEXPR int RTYPE = REALSXP;
-        static inline double NA() { return NA_REAL; }
-        static inline RCPP_CONSTEXPR double ZERO() { return 0.0; }
-        static inline RCPP_CONSTEXPR double ONE() { return 1.0; }
-    };
-
-    template<>
-    struct rtype_helper< int > {
-        typedef int type;
-        static RCPP_CONSTEXPR int RTYPE = INTSXP;
-        static inline int NA() { return NA_INTEGER; }
-        static inline RCPP_CONSTEXPR int ZERO() { return 0; }
-        static inline RCPP_CONSTEXPR int ONE() { return 1; }
-    };
-
-    template< typename T >
-    struct rtype {
-        typedef typename rtype_helper< typename traits::remove_const_and_reference< T >::type >::type type;
-        static RCPP_CONSTEXPR int RTYPE =
-            rtype_helper< typename traits::remove_const_and_reference< T >::type >::RTYPE;
-        static inline T NA() { return rtype_helper< typename traits::remove_const_and_reference< T >::type >::NA(); }
-        static inline RCPP_CONSTEXPR T ZERO() { return rtype_helper< typename traits::remove_const_and_reference< T >::type >::ZERO(); }
-        static inline RCPP_CONSTEXPR T ONE() { return rtype_helper< typename traits::remove_const_and_reference< T >::type >::ONE(); }
-    };
-
     typedef struct {char a[1];} CTYPE_CHAR;
     typedef struct {char a[2];} CTYPE_SHORT;
     typedef struct {char a[3];} CTYPE_INT;
@@ -157,6 +118,45 @@ namespace helpers {
         static const bool value = ctype_helper< sizeof(test(make())) >::value;
     };
 
+    template< typename T >
+    struct rtype_helper {
+        /*
+	typedef T type;
+        static RCPP_CONSTEXPR int RTYPE = REALSXP;
+        static inline double NA() { return NA_REAL; }
+        static inline RCPP_CONSTEXPR double ZERO() { return 0.0; }
+        static inline RCPP_CONSTEXPR double ONE() { return 1.0; }
+        */
+    };
+
+    template<>
+    struct rtype_helper< double > {
+        typedef double type;
+        static RCPP_CONSTEXPR int RTYPE = REALSXP;
+        static inline double NA() { return NA_REAL; }
+        static inline RCPP_CONSTEXPR double ZERO() { return 0.0; }
+        static inline RCPP_CONSTEXPR double ONE() { return 1.0; }
+    };
+
+    template<>
+    struct rtype_helper< int > {
+        typedef int type;
+        static RCPP_CONSTEXPR int RTYPE = INTSXP;
+        static inline int NA() { return NA_INTEGER; }
+        static inline RCPP_CONSTEXPR int ZERO() { return 0; }
+        static inline RCPP_CONSTEXPR int ONE() { return 1; }
+    };
+
+    template< typename T >
+    struct rtype {
+        typedef typename rtype_helper< typename ctype< T >::type >::type type;
+        typedef rtype_helper< typename ctype< T >::type > helper_type;
+        static RCPP_CONSTEXPR int RTYPE = helper_type::RTYPE;
+        static inline T NA() { return helper_type::NA(); }
+        static inline RCPP_CONSTEXPR T ZERO() { return helper_type::ZERO(); }
+        static inline RCPP_CONSTEXPR T ONE() { return helper_type::ONE(); }
+    };
+
     struct log {
         template< typename T >
         inline double operator()(T val) {