Remove the long since pointless complication of RowUsers and variable value caches

15 files changed, 65 insertions, 171 deletions

diff --git a/project2/Jamfile.jam b/project2/Jamfile.jam
index 035609b..5eb1c27 100644
--- a/project2/Jamfile.jam
+++ b/project2/Jamfile.jam
@@ -58,7 +58,7 @@ lib p2common :
 	iterate.cpp paramChecker.cpp presenter.cpp rawView.cpp logger.cpp if.cpp xmlScriptParser.cpp viewHost.cpp
 	sourceObject.cpp task.cpp variables.cpp variableConvert.cpp view.cpp xmlObjectLoader.cpp exceptions.cpp
 	sessionClearTask.cpp session.cpp sessionSetTask.cpp commonObjects.cpp xmlPresenter.cpp taskHost.cpp checkHost.cpp
-	rowView.cpp rowSet.cpp rowUser.cpp rowProcessor.cpp config.cpp fileStrmVarWriter.cpp noOutputExecute.cpp
+	rowView.cpp rowSet.cpp rowProcessor.cpp config.cpp fileStrmVarWriter.cpp noOutputExecute.cpp
 	transform.cpp transformHtml.cpp transformText.cpp definedColumns.cpp structExceptHandling.cpp validDateCheck.cpp
 	variables-modconfig.cpp
 	variables-modlookup.cpp
diff --git a/project2/iterate.cpp b/project2/iterate.cpp
index 1f2b12f..795b356 100644
--- a/project2/iterate.cpp
+++ b/project2/iterate.cpp
@@ -29,7 +29,6 @@ void
 Iterate::rowReady() const
 {
 	executeChildren();
-	source->rowChanged();
 }
 
 void
diff --git a/project2/rowSet.cpp b/project2/rowSet.cpp
index 1be3547..cfbb9cf 100644
--- a/project2/rowSet.cpp
+++ b/project2/rowSet.cpp
@@ -1,5 +1,4 @@
 #include "rowSet.h"
-#include "rowUser.h"
 #include "commonObjects.h"
 #include "logger.h"
 #include "variables.h"
@@ -19,18 +18,6 @@ RowSet::~RowSet()
 }
 
 void
-RowSet::use(const RowUser * r) const
-{
-	rowUsers.insert(r);
-}
-
-void
-RowSet::finish(const RowUser * r) const
-{
-	rowUsers.erase(r);
-}
-
-void
 RowSet::beginRow(const RowSet * r)
 {
 	stack.push_back(r);
@@ -46,14 +33,6 @@ RowSet::endRow(const RowSet * r)
 	stack.pop_back();
 }
 
-void
-RowSet::rowChanged() const
-{
-	BOOST_FOREACH(const RowUser * ru, rowUsers) {
-		ru->rowChanged();
-	}
-}
-
 VariableType
 RowSet::getRowNum() const
 {
diff --git a/project2/rowSet.h b/project2/rowSet.h
index 52edd76..a907cd2 100644
--- a/project2/rowSet.h
+++ b/project2/rowSet.h
@@ -9,7 +9,6 @@
 
 class RowProcessor;
 class RowSet;
-class RowUser;
 class VariableType;
 typedef boost::intrusive_ptr<RowSet> RowSetPtr;
 typedef boost::intrusive_ptr<const RowSet> ConstRowSetPtr;
@@ -35,21 +34,17 @@ class RowSet : public SourceObject {
 		virtual bool isNull(const Glib::ustring & id) const = 0;
 		VariableType getRowNum() const;
 		virtual void execute(const RowProcessor *) const = 0;
-		void use(const RowUser * r) const;
-		void finish(const RowUser * r) const;
 		virtual RowAttribute resolveAttr(const Glib::ustring & attrName) const;
 
 		static const RowValuesStack & Stack() { return stack; }
 		static void beginRow(const RowSet * r);
 		static void endRow(const RowSet * r);
-		void rowChanged() const;
 
 	protected:
 		mutable unsigned long int rowNum;
 
 	private:
 		static RowValuesStack stack;
-		mutable std::set<const RowUser *> rowUsers;
 };
 
 #endif
diff --git a/project2/rowUser.cpp b/project2/rowUser.cpp
deleted file mode 100644
index 2557af1..0000000
--- a/project2/rowUser.cpp
+++ /dev/null
@@ -1,10 +0,0 @@
-#include "rowUser.h"
-
-RowUser::RowUser()
-{
-}
-
-RowUser::~RowUser()
-{
-}
-
diff --git a/project2/rowUser.h b/project2/rowUser.h
deleted file mode 100644
index 9597807..0000000
--- a/project2/rowUser.h
+++ /dev/null
@@ -1,13 +0,0 @@
-#ifndef ROWUSER_H
-#define ROWUSER_H
-
-class RowUser {
-	public:
-		RowUser();
-		virtual ~RowUser() = 0;
-
-		virtual void rowChanged() const = 0;
-};
-
-#endif
-
diff --git a/project2/rowView.cpp b/project2/rowView.cpp
index cdbe071..8e22c4b 100644
--- a/project2/rowView.cpp
+++ b/project2/rowView.cpp
@@ -51,7 +51,6 @@ RowView::rowReady() const
 		}
 	}
 	executeChildren();
-	source->rowChanged();
 	presenter->popSub();
 }
 
diff --git a/project2/variables-modconfig.cpp b/project2/variables-modconfig.cpp
index 935e2d6..88fddd4 100644
--- a/project2/variables-modconfig.cpp
+++ b/project2/variables-modconfig.cpp
@@ -11,13 +11,9 @@ class VariableConfig : public VariableImplDyn {
 			name(e->get_attribute_value("name"))
 		{
 		}
-		const VariableType & value() const
+		VariableType value() const
 		{
-			if (!cacheValid) {
-				cache = ApplicationEngine::getCurrent()->getCurrentConfig()->getValue(name);
-				cacheValid = true;
-			}
-			return cache;
+			return ApplicationEngine::getCurrent()->getCurrentConfig()->getValue(name);
 		}
 	private:
 		const Glib::ustring name;
diff --git a/project2/variables-modlookup.cpp b/project2/variables-modlookup.cpp
index e020d9a..24c4167 100644
--- a/project2/variables-modlookup.cpp
+++ b/project2/variables-modlookup.cpp
@@ -64,7 +64,7 @@ class VariableLookup : public VariableImplDyn, public RowProcessor {
 			loader.supportedStorers.insert(Storer::into(&rowSets));
 			loader.collectAll(e, false);
 		}
-		const VariableType & value() const
+		VariableType value() const
 		{
 			if (map.empty()) {
 				fillCache();
@@ -76,8 +76,7 @@ class VariableLookup : public VariableImplDyn, public RowProcessor {
 			}
 			Map::const_iterator i = map.find(k);
 			if (i != map.end()) {
-				cache = i->second;
-				return cache;
+				return i->second;
 			}
 			throw NotFound();
 		}
diff --git a/project2/variables-modparam.cpp b/project2/variables-modparam.cpp
index a932412..0b205db 100644
--- a/project2/variables-modparam.cpp
+++ b/project2/variables-modparam.cpp
@@ -11,21 +11,17 @@ class VariableParam : public VariableImplDyn {
 			name(e->get_attribute_value("name"))
 		{
 		}
-		const VariableType & value() const
+		VariableType value() const
 		{
-			if (!cacheValid) {
-				try {
-					cache = ApplicationEngine::getCurrent()->env()->getParamQuery(name);
-				}
-				catch (ParamNotFound) {
-					if (!defaultValue) {
-						throw;
-					}
-					cache = (*defaultValue)();
+			try {
+				return ApplicationEngine::getCurrent()->env()->getParamQuery(name);
+			}
+			catch (ParamNotFound) {
+				if (!defaultValue) {
+					throw;
 				}
-				cacheValid = true;
+				return (*defaultValue)();
 			}
-			return cache;
 		}
 	private:
 		const Glib::ustring name;
diff --git a/project2/variables-modsession.cpp b/project2/variables-modsession.cpp
index 0d39695..963a105 100644
--- a/project2/variables-modsession.cpp
+++ b/project2/variables-modsession.cpp
@@ -11,18 +11,17 @@ class VariableSession : public VariableImplDyn {
 			name(e->get_attribute_value("name"))
 		{
 		}
-		const VariableType & value() const
+		VariableType value() const
 		{
 			try {
-				cache = ApplicationEngine::getCurrent()->session()->GetValue(name);
+				return ApplicationEngine::getCurrent()->session()->GetValue(name);
 			}
 			catch (Session::VariableNotFound) {
 				if (!defaultValue) {
 					throw;
 				}
-				cache = (*defaultValue)();
+				return (*defaultValue)();
 			}
-			return cache;
 		}
 	private:
 		const Glib::ustring name;
diff --git a/project2/variables-moduri.cpp b/project2/variables-moduri.cpp
index f6793e1..00fb7bf 100644
--- a/project2/variables-moduri.cpp
+++ b/project2/variables-moduri.cpp
@@ -11,21 +11,17 @@ class VariableUri : public VariableImplDyn {
 			index(atoi(e->get_attribute_value("index").c_str()))
 		{
 		}
-		const VariableType & value() const
+		VariableType value() const
 		{
-			if (!cacheValid) {
-				try {
-					cache = ApplicationEngine::getCurrent()->env()->getParamUri(index);
-				}
-				catch (UriElementOutOfRange) {
-					if (!defaultValue) {
-						throw;
-					}
-					cache = (*defaultValue)();
+			try {
+				return ApplicationEngine::getCurrent()->env()->getParamUri(index);
+			}
+			catch (UriElementOutOfRange) {
+				if (!defaultValue) {
+					throw;
 				}
-				cacheValid = true;
+				return (*defaultValue)();
 			}
-			return cache;
 		}
 	private:
 		unsigned int index;
diff --git a/project2/variables.cpp b/project2/variables.cpp
index 4e18fc0..516e187 100644
--- a/project2/variables.cpp
+++ b/project2/variables.cpp
@@ -4,7 +4,6 @@
 #include "exceptions.h"
 #include "appEngine.h"
 #include "session.h"
-#include "rowUser.h"
 #include "rowSet.h"
 #include <libxml++/nodes/textnode.h>
 #include <stdexcept>
@@ -132,117 +131,79 @@ class VariableLiteral : public VariableImpl {
 			}
 		}
 
-		virtual const VariableType & value() const { return val; }
+		virtual VariableType value() const { return val; }
 	private:
 		VariableType val;
 };
 DECLARE_COMPONENT_LOADER("literal", VariableLiteral, VariableLoader);
 DECLARE_CUSTOM_COMPONENT_LOADER("", VariableLiteralDef, VariableLoaderImpl<VariableLiteral>, VariableLoader);
 
-VariableImplDyn::VariableImplDyn(const xmlpp::Element * e) :
-	cacheValid(false)
+VariableImplDyn::VariableImplDyn(const xmlpp::Element * e)
 {
-	try {
-		if (e) {
-			defaultValue = Variable(e, "default");
-		}
-	}
-	catch (NoVariableDefinition) {
-		// That's cool... no default
+	if (e) {
+		defaultValue = Variable(e, "default", false);
 	}
 }
 
-static void assignHelper(VariableType & dest, const VariableType & src) {
-	dest = src;
-}
-
 /// Variable implementation to access fields in row sets
-class VariableParent : public VariableImplDyn, public RowUser {
+class VariableParent : public VariableImplDyn {
 	public:
-		VariableParent(const xmlpp::Element * e, const RowUser * d = NULL) :
+		VariableParent(const xmlpp::Element * e) :
 			VariableImplDyn(e),
-			row(NULL),
 			depth(atoi(e->get_attribute_value("depth").c_str())),
 			attr(e->get_attribute("attribute")),
-			name(attr ? e->get_attribute_value("attribute") : e->get_attribute_value("name")),
-			dep(d)
+			name(attr ? e->get_attribute_value("attribute") : e->get_attribute_value("name"))
 		{
 		}
 		VariableParent(const Glib::ustring & n, bool a, unsigned int d) :
 			VariableImplDyn(NULL),
-			row(NULL),
 			depth(d),
 			attr(a),
-			name(n),
-			dep(NULL)
+			name(n)
 		{
 		}
-		~VariableParent()
-		{
-			if (row) {
-				row->finish(this);
-				if (dep) {
-					row->finish(dep);
-				}
-			}
-		}
-		const VariableType & value() const
+		VariableType value() const
 		{
-			if (!cacheValid) {
-				try {
-					if (!row) {
-						RowSet::RowValuesStack::const_reverse_iterator r = RowSet::Stack().rbegin();
-						for (size_t p = depth; p--; r++) ;
-						if (r == RowSet::Stack().rend()) {
-							throw RowSet::ParentOutOfRange(depth);
-						}
-						row = *r;
-						row->use(this);
-						if (dep) {
-							row->use(dep);
-						}
-						bind();
+			try {
+				if (!getValue) {
+					RowSet::RowValuesStack::const_reverse_iterator r = RowSet::Stack().rbegin();
+					for (size_t p = depth; p--; r++) ;
+					if (r == RowSet::Stack().rend()) {
+						throw RowSet::ParentOutOfRange(depth);
 					}
-					getValue(cache, row);
+					;
+					bind(*r);
 				}
-				catch (RowSet::ParentOutOfRange) {
-					if (!defaultValue) {
-						throw;
-					}
-					cache = (*defaultValue)();
+				return getValue();
+			}
+			catch (RowSet::ParentOutOfRange) {
+				if (!defaultValue) {
+					throw;
 				}
-				catch (RowSet::FieldDoesNotExist) {
-					if (!defaultValue) {
-						throw;
-					}
-					cache = (*defaultValue)();
+				return (*defaultValue)();
+			}
+			catch (RowSet::FieldDoesNotExist) {
+				if (!defaultValue) {
+					throw;
 				}
-				cacheValid = true;
+				return (*defaultValue)();
 			}
-			return cache;
-		}
-		void rowChanged() const
-		{
-			cacheValid = false;
 		}
 	protected:
-		void bind() const
+		void bind(ConstRowSetPtr row) const
 		{
 			if (attr) {
-				getValue = boost::bind(&assignHelper, _1, boost::bind(row->resolveAttr(name)));
+				getValue = boost::bind(row->resolveAttr(name));
 			}
 			else {
 				typedef VariableType (RowSet::*gCV)(const Glib::ustring &) const;
-				getValue = boost::bind(&assignHelper, _1,
-						boost::bind((gCV)&RowSet::getCurrentValue, _2, name));
+				getValue = boost::bind((gCV)&RowSet::getCurrentValue, row, name);
 			}
 		}
-		mutable ConstRowSetPtr row;
 		const size_t depth;
 		const bool attr;
 		const Glib::ustring name;
-		const RowUser * dep;
-		mutable boost::function2<void, VariableType &, ConstRowSetPtr> getValue;
+		mutable boost::function0<VariableType> getValue;
 };
 DECLARE_COMPONENT_LOADER("parent", VariableParent, VariableLoader);
 
@@ -253,7 +214,7 @@ class VariableFixed : public VariableImpl {
 			var(v)
 		{
 		}
-		const VariableType & value() const
+		VariableType value() const
 		{
 			return var;
 		}
diff --git a/project2/variables.h b/project2/variables.h
index 92aac4b..a22ebf4 100644
--- a/project2/variables.h
+++ b/project2/variables.h
@@ -13,7 +13,6 @@
 #include <boost/variant.hpp>
 #include <boost/shared_ptr.hpp>
 
-class RowUser;
 class Null { };
 typedef boost::variant<
 	Null,
@@ -63,7 +62,7 @@ class VariableType : public _VT {
 /// Base class for Project2 variable accessors
 class VariableImpl : public IntrusivePtrBase {
 	public:
-		virtual const VariableType & value() const = 0;
+		virtual VariableType value() const = 0;
 
 	protected:
 		virtual ~VariableImpl() = 0;
@@ -79,13 +78,13 @@ class Variable {
 		static Variable makeFromCode(const Glib::ustring & s);
 		static Variable makeParent(const Glib::ustring & name, bool attr, unsigned int depth);
 
-		operator const VariableType & () const { return var->value(); }
-		const VariableType & operator()() const { return var->value(); }
+		operator VariableType () const { return var->value(); }
+		VariableType operator()() const { return var->value(); }
 
 	private:
 		Variable(VariableImpl *);
 		friend class VariableParse;
-		static VariableImplPtr create(const Glib::ustring & s, RowUser * dep = NULL);
+		static VariableImplPtr create(const Glib::ustring & s);
 		VariableImplPtr var;
 };
 
@@ -93,11 +92,9 @@ class Variable {
 class VariableImplDyn : public VariableImpl {
 	public:
 		VariableImplDyn(const xmlpp::Element * e);
-		virtual const VariableType & value() const = 0;
+		virtual VariableType value() const = 0;
 
 	protected:
-		mutable VariableType cache;
-		mutable bool cacheValid;
 		boost::optional<Variable> defaultValue;
 };
 
diff --git a/project2/xslRows.cpp b/project2/xslRows.cpp
index 9c4ce98..999f196 100644
--- a/project2/xslRows.cpp
+++ b/project2/xslRows.cpp
@@ -98,11 +98,12 @@ XslRows::execute(const RowProcessor * rp) const
 		xpathCtx->node = rowRoot;
 		values.clear();
 		BOOST_FOREACH(const FilterView::XPaths::value_type & xp, fv->xpaths) {
-			if (boost::get<Null>(&xp.second())) {
+			VariableType path(xp.second());
+			if (boost::get<Null>(&path)) {
 				values[xp.first] = Null();
 				continue;
 			}
-			xmlXPathObjectSPtr xpathObjI = xmlXPathObjectSPtr(xmlXPathEvalExpression(xp.second(), xpathCtx.get()), xmlXPathFreeObject);
+			xmlXPathObjectSPtr xpathObjI = xmlXPathObjectSPtr(xmlXPathEvalExpression(path, xpathCtx.get()), xmlXPathFreeObject);
 			if (!xpathObjI) {
 				throw XpathEvalError(xmlGetLastError()->message);
 			}