Handy little lazy pointer class for last minute default initialisation

3 files changed, 12 insertions, 21 deletions

diff --git a/project2/cgi/cgiAppEngine.h b/project2/cgi/cgiAppEngine.h
index 854013a..66d5a69 100644
--- a/project2/cgi/cgiAppEngine.h
+++ b/project2/cgi/cgiAppEngine.h
@@ -8,6 +8,7 @@
 #include "taskHost.h"
 #include "viewHost.h"
 #include "transform.h"
+#include "lazyPointer.h"
 #include "xmlPresenter.h"
 #include "presenterCache.h"
 #include "sessionContainer.h"
@@ -104,7 +105,7 @@ class CgiApplicationEngine : public ApplicationEngine, public TransformChainLink
 				virtual HttpHeaderPtr getHeader() const;
 			protected:
 				HttpHeaderPtr header;
-				mutable MultiRowSetPresenterPtr presenter;
+				LazyPointer<MultiRowSetPresenter> presenter;
 		};
 
 		/// Stage to return previous cached output
diff --git a/project2/cgi/cgiStagePresent.cpp b/project2/cgi/cgiStagePresent.cpp
index 98031e4..9574e84 100644
--- a/project2/cgi/cgiStagePresent.cpp
+++ b/project2/cgi/cgiStagePresent.cpp
@@ -9,7 +9,8 @@ CgiApplicationEngine::PresentStage::PresentStage(ScriptReaderPtr s) :
 	CgiApplicationEngine::ResponseStage(s->root()),
 	CommonObjects(s->root()),
 	CheckHost(s->root()),
-	ViewHost(s->root())
+	ViewHost(s->root()),
+	presenter([root,this] { return PresenterLoader::getFor(this->env()->defaultPresenter)->create(root); })
 {
 	s->loader.addLoadTarget(s->root(), Storer::into<OutputOptionsLoader>(&outputOptions));
 	s->loader.addLoadTarget(s->root(), Storer::into<PresenterLoader>(&presenter));
@@ -51,9 +52,6 @@ CgiApplicationEngine::PresentStage::run()
 MultiRowSetPresenterPtr
 CgiApplicationEngine::PresentStage::getPresenter() const
 {
-	if (!presenter) {
-		presenter = PresenterLoader::getFor(env()->defaultPresenter)->create(root);
-	}
 	return presenter;
 }
 
diff --git a/project2/common/scriptStorage.h b/project2/common/scriptStorage.h
index 63ee71c..12cf3a6 100644
--- a/project2/common/scriptStorage.h
+++ b/project2/common/scriptStorage.h
@@ -14,8 +14,6 @@
 
 SimpleMessageException(StoreFailed);
 
-#define SINGLE(X) \
-	boost::intrusive_ptr<X>
 #define STORAGEOF(X) \
 	std::map<std::string, boost::intrusive_ptr<X> >
 #define ANONORDEREDSTORAGEOF(X) \
@@ -29,8 +27,8 @@ class StorerBase;
 typedef boost::intrusive_ptr<Storer> StorerPtr;
 class Storer : public virtual IntrusivePtrBase {
 	public:
-		template <class L, class X, typename... C>
-		static boost::intrusive_ptr<StorerBase<X, L> > into(SINGLE(X) * obj, const C & ... c);
+		template <class L, typename PtrOfX, typename... C>
+		static boost::intrusive_ptr<StorerBase<typename PtrOfX::element_type, L> > into(PtrOfX * obj, const C & ... c);
 		template <class L, class X, typename... C>
 		static boost::intrusive_ptr<StorerBase<X, L> > into(STORAGEOF(X) * map, const C & ... c);
 		template <class L, class X, typename... C>
@@ -70,14 +68,8 @@ class StorerBase : public Storer {
 template <class X, class M, class L>
 class StorerImpl : public StorerBase<X, L> {
 	public:
-		StorerImpl(M * m);
-		bool insert(boost::intrusive_ptr<X> O);
-};
-template <class X, class L>
-class StorerImpl<X, SINGLE(X), L> : public StorerBase<X, L> {
-	public:
-		typedef SINGLE(X) Obj;
-		StorerImpl(SINGLE(X) * o, const typename StorerBase<X, L>::Creator & c) : StorerBase<X, L>(c), obj(o)
+		typedef M Obj;
+		StorerImpl(M * o, const typename StorerBase<X, L>::Creator & c) : StorerBase<X, L>(c), obj(o)
 		{
 		}
 		bool insert(boost::intrusive_ptr<X> O)
@@ -129,10 +121,10 @@ class StorerImpl<X, ANONORDEREDSTORAGEOF(X), L> : public StorerBase<X, L> {
 		Map * map;
 };
 
-template <class L, class X, typename... C>
-boost::intrusive_ptr<StorerBase<X, L> >
-Storer::into(SINGLE(X) * obj, const C & ... c) {
-	return new StorerImpl<X, SINGLE(X), L>(obj, boost::bind(&L::create, _1, _2, c...));
+template <class L, class PtrOfX, typename... C>
+boost::intrusive_ptr<StorerBase<typename PtrOfX::element_type, L> >
+Storer::into(PtrOfX * obj, const C & ... c) {
+	return new StorerImpl<typename PtrOfX::element_type, PtrOfX, L>(obj, boost::bind(&L::create, _1, _2, c...));
 }
 
 template <class L, class X, typename... C>