change handling of const pointers in SysCopyHandle

Essentially I now need to include the const modifier directly in the
template type.  The idea is that this allows future iterations of the
handle to do different things based on whether they will provide read
access or update access.

PhysicsAnalysis/Algorithms/JetAnalysisAlgorithms/JetAnalysisAlgorithms/JetDecoratorAlg.h

@@ -42,7 +42,7 @@ namespace CP
 
     /// \brief the jet collection we run on
   private:
-    SysCopyHandle<xAOD::JetContainer> m_jetHandle {
+    SysCopyHandle<const xAOD::JetContainer> m_jetHandle {
       this, "jets", "", "the jet collection to run on"};
 
   };

PhysicsAnalysis/Algorithms/SystematicsHandles/SystematicsHandles/SysCopyHandle.h

@@ -91,12 +91,6 @@ namespace CP
                           const CP::SystematicSet& sys) const;
 
 
-    /// \brief const retrieve the object for the given name
-  public:
-    ::StatusCode getCopy (const T*& object,
-                          const CP::SystematicSet& sys) const;
-
-
 
     //
     // inherited interface

PhysicsAnalysis/Algorithms/SystematicsHandles/SystematicsHandles/SysCopyHandle.icc

@@ -100,6 +100,7 @@ namespace CP
     if (std::get<1>(cache->second).empty())
     {
       // if no output name is configured, act like an update handle
+      // (or read handle if const qualified)
       return m_evtStore->retrieve (object, std::get<0>(cache->second));
     } else
     {
@@ -111,43 +112,12 @@ namespace CP
       if (m_evtStore->retrieve (inputObject, std::get<0>(cache->second)).isFailure())
         return StatusCode::FAILURE;
 
-      return detail::ShallowCopy<T>::getCopy
-        (msg(), *m_evtStore, object, inputObject,
-         std::get<1>(cache->second), std::get<2>(cache->second));
-    }
-  }
-
-  template<typename T> ::StatusCode SysCopyHandle<T> ::
-  getCopy (const T*& object, const CP::SystematicSet& sys) const
-  {
-    auto cache = m_nameCache.find (sys);
-    if (cache == m_nameCache.end())
-    {
-      if (m_nameCache.empty())
-        throw std::logic_error ("uninitialized SysCopyHandle (" + m_inputName + ")");
-      else
-        throw std::logic_error ("unsupported systematic in SysCopyHandle (" + m_inputName + "): (" + sys.name() + ")");
-    }
-    assert (m_evtStore);
-    if (std::get<1>(cache->second).empty())
-    {
-      // if no output name is configured, act like an update handle
-      return m_evtStore->retrieve (object, std::get<0>(cache->second));
-    } else
-    {
-      // if an output name is configured, retrieve the input object as
-      // a const object, (shallow) copy it, record the copy and return
-      // it.
-
-      const T *inputObject = nullptr;
-      if (m_evtStore->retrieve (inputObject, std::get<0>(cache->second)).isFailure())
-        return StatusCode::FAILURE;
-
-      T *tmpObject = nullptr;
-
-      if (detail::ShallowCopy<T>::getCopy
-        (msg(), *m_evtStore, tmpObject, inputObject,
-         std::get<1>(cache->second), std::get<2>(cache->second)).isFailure())
+      // using an intermediate, since in the const version we can't
+      // pass in our argument pointer
+      std::remove_const_t<T> *tmpObject = nullptr;
+      if (detail::ShallowCopy<std::remove_const_t<T>>::getCopy
+          (msg(), *m_evtStore, tmpObject, inputObject,
+           std::get<1>(cache->second), std::get<2>(cache->second)).isFailure())
         return StatusCode::FAILURE;
       object = tmpObject;
       return StatusCode::SUCCESS;