ENH: Avoid use of boost::get for isInitialized()

Replace with visitor pattern that avoids the need for catching the exception.
Update the HDF5Writer to use stringstreams for error message output for
concatenating strings and error codes.

core/XdmfArray.cpp

@@ -441,6 +441,34 @@ private:
   XdmfArray * const mArray;
 };
 
+class XdmfArray::IsInitialized : public boost::static_visitor<bool> {
+public:
+
+  IsInitialized()
+  {
+  }
+
+  bool
+  operator()(const boost::blank & array) const
+  {
+    return false;
+  }
+
+  template<typename T>
+  bool
+  operator()(const shared_ptr<std::vector<T> > & array) const
+  {
+    return true;
+  }
+
+  template<typename T>
+  bool
+  operator()(const boost::shared_array<const T> & array) const
+  {
+    return true;
+  }
+};
+
 class XdmfArray::Reserve : public boost::static_visitor<void> {
 public:
 
@@ -739,13 +767,8 @@ XdmfArray::insert(const unsigned int startIndex,
 bool
 XdmfArray::isInitialized() const
 {
-  try {
-    boost::get<boost::blank>(mArray);
-    return false;
-  }
-  catch(const boost::bad_get & exception) {
-  }
-  return true;
+  return boost::apply_visitor(IsInitialized(),
+                              mArray);
 }
 
 void

core/XdmfArray.hpp

@@ -501,6 +501,7 @@ private:
   template <typename T> class Insert;
   class InsertArray;
   class InternalizeArrayPointer;
+  class IsInitialized;
   struct NullDeleter;
   template <typename T> class PushBack;
   class Reserve;

core/XdmfArray.tpp

@@ -800,7 +800,7 @@ XdmfArray::swap(std::vector<T> & array)
     currArray->swap(array);
     return true;
   }
-  catch(const boost::bad_get& exception) {
+  catch(const boost::bad_get & exception) {
     return false;
   }
 }

core/XdmfHDF5Writer.cpp

@@ -343,9 +343,11 @@ XdmfHDF5Writer::write(XdmfArray & array,
                           property,
                           H5P_DEFAULT);
       if(dataset < 0) {
+        std::stringstream error;
+        error << "H5Dcreate returned failure in XdmfHDF5Writer::write -- " 
+              << "dataset: " << dataset;
         XdmfError::message(XdmfError::FATAL,
-                           "H5Dcreate returned failure in "
-                           "XdmfHDF5Writer::write -- status: " + dataset);
+                           error.str());
       }
       status = H5Pclose(property);
     }
@@ -420,9 +422,11 @@ XdmfHDF5Writer::write(XdmfArray & array,
                                    NULL) ;
       
       if(status < 0) {
+        std::stringstream error;
+        error << "H5Dset_extent returned failure in XdmfHDF5Writer::write "
+              << "-- status: " << status;
         XdmfError::message(XdmfError::FATAL,
-                           "H5Dset_extent returned failure in "
-                           "XdmfHDF5Writer::write -- status: " + status);
+                           error.str());
       }
     }
 
@@ -434,9 +438,11 @@ XdmfHDF5Writer::write(XdmfArray & array,
                       array.getValuesInternal());
 
     if(status < 0) {
+      std::stringstream error;
+      error << "H5Dwrite returned failure in XdmfHDF5Writer::write "
+            << "-- status: " << status;
       XdmfError::message(XdmfError::FATAL, 
-                         "H5Dwrite returned failure in XdmfHDF5Writer::write "
-                         "-- status: " + status);
+                         error.str());
     }
 
     if(dataspace != H5S_ALL) {