From fbf104f5c4804606b9e4e1e1a9ff3c62336a1b8d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kirill=20M=C3=BCller?= <krlmlr@users.noreply.github.com>
Date: Wed, 13 Jan 2016 14:08:55 +0100
Subject: [PATCH 1/5] const support for Nullable

cargo-culted from many other implementations of `operator SEXP()`
---
 inst/include/Rcpp/Nullable.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/inst/include/Rcpp/Nullable.h b/inst/include/Rcpp/Nullable.h
index 67c02f0cc..5bbc0f183 100644
--- a/inst/include/Rcpp/Nullable.h
+++ b/inst/include/Rcpp/Nullable.h
@@ -76,7 +76,7 @@ namespace Rcpp {
          *
          * @throw 'not initialized' if object has not been set
          */
-        inline operator SEXP() {
+        inline operator SEXP() const {
             checkIfSet();
             return m_sexp;
         }
@@ -86,7 +86,7 @@ namespace Rcpp {
          *
          * @throw 'not initialized' if object has not been set
          */
-        inline SEXP get() {
+        inline SEXP get() const {
             checkIfSet();
             return m_sexp;
         }

From 324e75c9a7f18568fc373394b90e630a3a1815bb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kirill=20M=C3=BCller?= <kirill.mueller@ivt.baug.ethz.ch>
Date: Wed, 13 Jan 2016 14:15:57 +0100
Subject: [PATCH 2/5] operator SEXP() is forwarded to get()

---
 inst/include/Rcpp/Nullable.h | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/inst/include/Rcpp/Nullable.h b/inst/include/Rcpp/Nullable.h
index 5bbc0f183..c9a4da63e 100644
--- a/inst/include/Rcpp/Nullable.h
+++ b/inst/include/Rcpp/Nullable.h
@@ -77,8 +77,7 @@ namespace Rcpp {
          * @throw 'not initialized' if object has not been set
          */
         inline operator SEXP() const {
-            checkIfSet();
-            return m_sexp;
+            return get();
         }
 
         /**

From ff00bf7353e54b0989567be1ea9320f450f9c999 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kirill=20M=C3=BCller?= <kirill.mueller@ivt.baug.ethz.ch>
Date: Wed, 13 Jan 2016 14:20:43 +0100
Subject: [PATCH 3/5] use const& in Nullable tests

---
 inst/unitTests/cpp/misc.cpp | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/inst/unitTests/cpp/misc.cpp b/inst/unitTests/cpp/misc.cpp
index 452e8c872..eab3ecb14 100644
--- a/inst/unitTests/cpp/misc.cpp
+++ b/inst/unitTests/cpp/misc.cpp
@@ -179,22 +179,22 @@ void test_stop_variadic() {
 }
 
 // [[Rcpp::export]]
-bool testNullableForNull(Nullable<NumericMatrix> M) {
+bool testNullableForNull(const Nullable<NumericMatrix>& M) {
     return M.isNull();
 }
 
 // [[Rcpp::export]]
-bool testNullableForNotNull(Nullable<NumericMatrix> M) {
+bool testNullableForNotNull(const Nullable<NumericMatrix>& M) {
     return M.isNotNull();
 }
 
 // [[Rcpp::export]]
-SEXP testNullableOperator(Nullable<NumericMatrix> M) {
+SEXP testNullableOperator(const Nullable<NumericMatrix>& M) {
     return M;
 }
 
 // [[Rcpp::export]]
-SEXP testNullableGet(Nullable<NumericMatrix> M) {
+SEXP testNullableGet(const Nullable<NumericMatrix>& M) {
     return M.get();
 }
 

From 563d9683f70c873acbd284b5641e4479f7be2d68 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kirill=20M=C3=BCller?= <kirill.mueller@ivt.baug.ethz.ch>
Date: Wed, 13 Jan 2016 14:25:48 +0100
Subject: [PATCH 4/5] NEWS

---
 inst/NEWS.Rd | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/inst/NEWS.Rd b/inst/NEWS.Rd
index bea986564..694688fa8 100644
--- a/inst/NEWS.Rd
+++ b/inst/NEWS.Rd
@@ -3,6 +3,17 @@
 \newcommand{\ghpr}{\href{https://github.com/RcppCore/Rcpp/pull/#1}{##1}}
 \newcommand{\ghit}{\href{https://github.com/RcppCore/Rcpp/issues/#1}{##1}}
 
+\section{Changes in Rcpp version 0.12.4 (2016-01-XX)}{
+  \itemize{
+    \item Changes in Rcpp API:
+    \itemize{
+      \item \code{Nullable<>::operator SEXP()} and
+      \code{Nullable<>::get()} now also work for \code{const} objects
+      (PR \ghpr{417}).
+    }
+  }
+}
+
 \section{Changes in Rcpp version 0.12.3 (2016-01-10)}{
   \itemize{
     \item Changes in Rcpp API:

From 2c57b986f74609b2621ece5b434d4785462779a5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kirill=20M=C3=BCller?= <kirill.mueller@ivt.baug.ethz.ch>
Date: Wed, 13 Jan 2016 14:55:56 +0100
Subject: [PATCH 5/5] Revert "operator SEXP() is forwarded to get()"

This reverts commit 324e75c9a7f18568fc373394b90e630a3a1815bb.
---
 inst/include/Rcpp/Nullable.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/inst/include/Rcpp/Nullable.h b/inst/include/Rcpp/Nullable.h
index c9a4da63e..5bbc0f183 100644
--- a/inst/include/Rcpp/Nullable.h
+++ b/inst/include/Rcpp/Nullable.h
@@ -77,7 +77,8 @@ namespace Rcpp {
          * @throw 'not initialized' if object has not been set
          */
         inline operator SEXP() const {
-            return get();
+            checkIfSet();
+            return m_sexp;
         }
 
         /**