Support getting a reference to a child, for access to its metadata, and then GetChild wraps that

5 files changed, 115 insertions, 27 deletions

diff --git a/slicer/json/Jamfile.jam b/slicer/json/Jamfile.jam
index 0a0b02a..beb6679 100644
--- a/slicer/json/Jamfile.jam
+++ b/slicer/json/Jamfile.jam
@@ -20,6 +20,7 @@ lib slicer-json :
 	<library>IceUtil
 	<library>jsonpp
 	<library>glibmm
+	<library>../slicer//slicer
 	: :
 	<library>jsonpp
 	;
diff --git a/slicer/slicer/modelParts.cpp b/slicer/slicer/modelParts.cpp
index e2711a1..b070bef 100644
--- a/slicer/slicer/modelParts.cpp
+++ b/slicer/slicer/modelParts.cpp
@@ -91,6 +91,20 @@ namespace Slicer {
 		return emptyMetadata;
 	}
 
+	ModelPartPtr
+	ModelPart::GetChild(const HookFilter & flt)
+	{
+		auto ref = GetChildRef(flt);
+		return ref ? ref->Child() : ModelPartPtr(NULL);
+	}
+
+	ModelPartPtr
+	ModelPart::GetChild(const std::string & memberName, const HookFilter & flt)
+	{
+		auto ref = GetChildRef(memberName, flt);
+		return ref ? ref->Child() : ModelPartPtr(NULL);
+	}
+
 	template<> std::string Slicer::ModelPartForRoot<std::string>::rootName = "String";
 	template<> std::string Slicer::ModelPartForRoot<bool>::rootName = "Boolean";
 	template<> std::string Slicer::ModelPartForRoot<Ice::Float>::rootName = "Float";
diff --git a/slicer/slicer/modelParts.h b/slicer/slicer/modelParts.h
index 9386696..9027f92 100644
--- a/slicer/slicer/modelParts.h
+++ b/slicer/slicer/modelParts.h
@@ -137,13 +137,46 @@ namespace Slicer {
 #undef templateMODELPARTFOR
 #undef MODELPARTFOR
 
+	class ChildRef : public IceUtil::Shared {
+		public:
+			virtual ModelPartPtr Child() const = 0;
+			virtual const Metadata & ChildMetaData() const = 0;
+	};
+	typedef IceUtil::Handle<ChildRef> ChildRefPtr;
+	class DirectChildRef : public ChildRef {
+		public:
+			DirectChildRef(ModelPartPtr);
+
+			ModelPartPtr Child() const;
+			const Metadata & ChildMetaData() const;
+
+		private:
+			ModelPartPtr mpp;
+	};
+	class FunctionChildRef : public ChildRef {
+		public:
+			typedef boost::function<ModelPartPtr()> ModelPartFunc;
+			typedef boost::function<const Metadata &()> MetadataFunc;
+
+			FunctionChildRef(const ModelPartFunc &, const MetadataFunc &);
+
+			ModelPartPtr Child() const;
+			const Metadata & ChildMetaData() const;
+
+		private:
+			ModelPartFunc mpf;
+			MetadataFunc mdf;
+	};
+
 	class ModelPart : public IceUtil::Shared {
 		public:
 			virtual ~ModelPart() = default;
 
 			virtual void OnEachChild(const ChildHandler &) = 0;
-			virtual ModelPartPtr GetChild(const HookFilter & = HookFilter()) = 0;
-			virtual ModelPartPtr GetChild(const std::string & memberName, const HookFilter & = HookFilter()) = 0;
+			ModelPartPtr GetChild(const HookFilter & = HookFilter());
+			ModelPartPtr GetChild(const std::string & memberName, const HookFilter & = HookFilter());
+			virtual ChildRefPtr GetChildRef(const HookFilter & = HookFilter()) = 0;
+			virtual ChildRefPtr GetChildRef(const std::string & memberName, const HookFilter & = HookFilter()) = 0;
 			virtual ModelPartPtr GetSubclassModelPart(const std::string &);
 			virtual TypeId GetTypeId() const;
 			virtual IceUtil::Optional<std::string> GetTypeIdProperty() const;
@@ -173,8 +206,8 @@ namespace Slicer {
 			{
 			}
 			virtual void OnEachChild(const ChildHandler &) { }
-			virtual ModelPartPtr GetChild(const HookFilter &) override { return NULL; }
-			virtual ModelPartPtr GetChild(const std::string &, const HookFilter &) override { return NULL; }
+			virtual ChildRefPtr GetChildRef(const HookFilter &) override { return NULL; }
+			virtual ChildRefPtr GetChildRef(const std::string &, const HookFilter &) override { return NULL; }
 			virtual void SetValue(ValueSourcePtr s) override { s->set(Member); }
 			virtual void GetValue(ValueTargetPtr s) override { s->get(Member); }
 			virtual bool HasValue() const override { return true; }
@@ -198,8 +231,8 @@ namespace Slicer {
 			{
 			}
 			virtual void OnEachChild(const ChildHandler &) { }
-			virtual ModelPartPtr GetChild(const HookFilter &) override { return NULL; }
-			virtual ModelPartPtr GetChild(const std::string &, const HookFilter &) override { return NULL; }
+			virtual ChildRefPtr GetChildRef(const HookFilter &) override { return NULL; }
+			virtual ChildRefPtr GetChildRef(const std::string &, const HookFilter &) override { return NULL; }
 			virtual void SetValue(ValueSourcePtr s) override;
 			virtual void GetValue(ValueTargetPtr s) override;
 			virtual bool HasValue() const override { return true; }
@@ -246,17 +279,17 @@ namespace Slicer {
 					modelPart->Create();
 				}
 			}
-			virtual ModelPartPtr GetChild(const HookFilter & flt) override
+			virtual ChildRefPtr GetChildRef(const HookFilter & flt) override
 			{
 				if (OptionalMember) {
-					return modelPart->GetChild(flt);
+					return modelPart->GetChildRef(flt);
 				}
 				return NULL;
 			}
-			virtual ModelPartPtr GetChild(const std::string & name, const HookFilter & flt) override
+			virtual ChildRefPtr GetChildRef(const std::string & name, const HookFilter & flt) override
 			{
 				if (OptionalMember) {
-					return modelPart->GetChild(name, flt);
+					return modelPart->GetChildRef(name, flt);
 				}
 				return NULL;
 			}
@@ -340,20 +373,24 @@ namespace Slicer {
 				}
 			}
 
-			virtual ModelPartPtr GetChild(const HookFilter & flt) override
+			virtual ChildRefPtr GetChildRef(const HookFilter & flt) override
 			{
 				for (const auto & h : hooks) {
 					if (!flt || flt(h)) {
-						return h->Get(GetModel());
+						return new FunctionChildRef(
+								boost::bind(&HookBase::Get, h, GetModel()),
+								boost::bind(&HookBase::GetMetadata, h));
 					}
 				}
 				return NULL;
 			}
-			ModelPartPtr GetChild(const std::string & name, const HookFilter & flt) override
+			ChildRefPtr GetChildRef(const std::string & name, const HookFilter & flt) override
 			{
 				for (const auto & h : hooks) {
 					if (h->PartName() == name && (!flt || flt(h))) {
-						return h->Get(GetModel());
+						return new FunctionChildRef(
+								boost::bind(&HookBase::Get, h, GetModel()),
+								boost::bind(&HookBase::GetMetadata, h));
 					}
 				}
 				return NULL;
@@ -467,19 +504,19 @@ namespace Slicer {
 				}
 			}
 
-			virtual ModelPartPtr GetChild(const HookFilter &) override
+			virtual ChildRefPtr GetChildRef(const HookFilter &) override
 			{
 				mp->Create();
-				return mp;
+				return new DirectChildRef(mp);
 			}
 
-			virtual ModelPartPtr GetChild(const std::string & name, const HookFilter &) override
+			virtual ChildRefPtr GetChildRef(const std::string & name, const HookFilter &) override
 			{
 				if (name != rootName) {
 					throw IncorrectElementName(name);
 				}
 				mp->Create();
-				return mp;
+				return new DirectChildRef(mp);
 			}
 
 			virtual void OnEachChild(const ChildHandler & ch) override
@@ -528,13 +565,13 @@ namespace Slicer {
 				}
 			}
 
-			ModelPartPtr GetChild(const HookFilter &) override
+			ChildRefPtr GetChildRef(const HookFilter &) override
 			{
 				sequence.push_back(typename element_type::value_type());
-				return ModelPartFor(sequence.back());
+				return new DirectChildRef(ModelPartFor(sequence.back()));
 			}
 
-			ModelPartPtr GetChild(const std::string &, const HookFilter &) override;
+			ChildRefPtr GetChildRef(const std::string &, const HookFilter &) override;
 
 			virtual bool HasValue() const override { return true; }
 
@@ -610,17 +647,17 @@ namespace Slicer {
 				}
 			}
 
-			ModelPartPtr GetChild(const HookFilter &) override
+			ChildRefPtr GetChildRef(const HookFilter &) override
 			{
-				return new ModelPartForDictionaryElementInserter<T>(dictionary);
+				return new DirectChildRef(new ModelPartForDictionaryElementInserter<T>(dictionary));
 			}
 
-			ModelPartPtr GetChild(const std::string & name, const HookFilter &) override
+			ChildRefPtr GetChildRef(const std::string & name, const HookFilter &) override
 			{
 				if (name != pairName) {
 					throw IncorrectElementName(name);
 				}
-				return new ModelPartForDictionaryElementInserter<T>(dictionary);
+				return new DirectChildRef(new ModelPartForDictionaryElementInserter<T>(dictionary));
 			}
 
 			virtual bool HasValue() const override { return true; }
diff --git a/slicer/slicer/parser.cpp b/slicer/slicer/parser.cpp
index 467f0ba..0e00dc1 100644
--- a/slicer/slicer/parser.cpp
+++ b/slicer/slicer/parser.cpp
@@ -294,7 +294,7 @@ namespace Slicer {
 
 		fprintf(cpp, "// Sequence %s\n", s->name().c_str());
 		fprintf(cpp, "template<>\n");
-		fprintf(cpp, "ModelPartPtr ModelPartForSequence< %s >::GetChild(const std::string & name, const HookFilter & flt)\n{\n",
+		fprintf(cpp, "ChildRefPtr ModelPartForSequence< %s >::GetChildRef(const std::string & name, const HookFilter & flt)\n{\n",
 				s->scoped().c_str());
 		auto iname = metaDataValue("slicer:item:", s->getMetaData());
 		if (iname) {
@@ -304,7 +304,7 @@ namespace Slicer {
 		else {
 			fprintf(cpp, "\t(void)name;\n");
 		}
-		fprintf(cpp, "\treturn GetChild(flt);\n}\n\n");
+		fprintf(cpp, "\treturn GetChildRef(flt);\n}\n\n");
 
 		fprintf(cpp, "template<>\n");
 		fprintf(cpp, "ModelPartPtr\n");
diff --git a/slicer/slicer/slicer.cpp b/slicer/slicer/slicer.cpp
index c055565..3af8bea 100644
--- a/slicer/slicer/slicer.cpp
+++ b/slicer/slicer/slicer.cpp
@@ -1,6 +1,7 @@
 #include "slicer.h"
 
 namespace Slicer {
+	const Metadata emptyMetadata;
 #define MODELPARTFOR(Type, ModelPart) \
 	ModelPartPtr ModelPartFor(Type & t) { return new ModelPart< Type >(t); } \
 	ModelPartPtr ModelPartFor(Type * t) { return new ModelPart< Type >(t); }
@@ -13,5 +14,40 @@ namespace Slicer {
 	MODELPARTFOR(Ice::Int, ModelPartForSimple);
 	MODELPARTFOR(Ice::Long, ModelPartForSimple);
 #undef MODELPARTFOR
+
+	Slicer::FunctionChildRef::FunctionChildRef(const Slicer::FunctionChildRef::ModelPartFunc & mp, const Slicer::FunctionChildRef::MetadataFunc & md) :
+		mpf(mp),
+		mdf(md)
+	{
+	}
+
+	ModelPartPtr
+	Slicer::FunctionChildRef::Child() const
+	{
+		return mpf();
+	}
+
+	const Metadata &
+	Slicer::FunctionChildRef::ChildMetaData() const
+	{
+		return mdf();
+	}
+
+	Slicer::DirectChildRef::DirectChildRef(ModelPartPtr m) :
+		mpp(m)
+	{
+	}
+
+	ModelPartPtr
+	Slicer::DirectChildRef::Child() const
+	{
+		return mpp;
+	}
+
+	const Metadata &
+	Slicer::DirectChildRef::ChildMetaData() const
+	{
+		return emptyMetadata;
+	}
 }