diff --git a/runtime/main.cpp b/runtime/main.cpp
index a212d59..dbbf58d 100644
--- a/runtime/main.cpp
+++ b/runtime/main.cpp
@@ -5,6 +5,24 @@
 */
 #include "runtime.h"
 
+struct subroutine *callStack=nullptr;
+
+subroutine::subroutine(enum STATES r)
+{
+	this->ret=r;
+	this->called=callStack;
+}
+
+enum STATES subroutine::close()
+{
+	if (callStack==nullptr) return STACK_UNDERFLOW_ERROR;
+	enum STATES r=callStack->ret;
+	struct subroutine *l=callStack->called;
+	delete callStack;
+	callStack=l;
+	return r;
+}
+
 int main(int argc, char *argv[])
 {
 	unsigned int ret=run();
diff --git a/runtime/runtime.h b/runtime/runtime.h
index 3a1435a..ae2c8a7 100644
--- a/runtime/runtime.h
+++ b/runtime/runtime.h
@@ -14,9 +14,24 @@ enum STATES:unsigned int
 {
     EXIT,
     UNDEFINED_STATE_ERROR,
+    STACK_UNDERFLOW_ERROR,
     START
 };
 
+class subroutine
+{
+    struct subroutine *called;
+    enum STATES ret;
+
+public:
+    static enum STATES close();
+    subroutine(enum STATES r);
+    virtual ~subroutine()
+    {}
+};
+
+extern struct subroutine *callStack;
+
 /* function prototype */
 unsigned int run();
 
diff --git a/tester.cpp b/tester.cpp
index 21132e7..dcd8f03 100644
--- a/tester.cpp
+++ b/tester.cpp
@@ -72,6 +72,7 @@ const string CODETYPES[]={
 enum COMPILE_ERRORS errorLevel=E_OK;
 unsigned int indentLevel=0;
 bool scopeGlobal=true;
+unsigned int currentFunc=0;
 
 bool COMPILE=false;
 bool DUMP=false;
@@ -201,7 +202,7 @@ void setUp()
 	{
 		varNames.open("/dev/null");
 	}
-	if (DEBUG)
+	if (DEBUG || TRACE)
 	{
 		/* dump identifier mode */
 		logfile.open("parse.log");
@@ -237,7 +238,7 @@ void logger(string s)
 	if (DEBUG)
 	{
 		indent();
-		logfile << s << "\n";
+		logfile << s << endl;
 	}
 }
 
@@ -246,12 +247,11 @@ void shutDown()
 {
 	if  (errorLevel != E_OK) cerr << "\nERROR: " 
 		<< COMPILE_ERROR_NAMES[errorLevel] << "\n\n" << endl;
-	logger("Purging tempVar queues");
+	logger("Shutting Down:  Purging tempVar queues");
 	tempVar::eraseQueues();
-	logger("Dumping stack.");
-	if (DUMP && (logfile)) fn::dumpCallStack();
 	if (DUMP)
 	{
+		fn::dumpFunctionIDs();
 		varNames << "Global Variables\n";
 		for(auto iter=globals.begin(); iter!=globals.end(); ++iter)
 		{
@@ -276,18 +276,29 @@ void shutDown()
 
 variableType *v;
 printSegment *print;
+fn *func;
+operands *o;
+expression *e;
+list<operands *>p;
 void testInt()
 {
+	logger("testInt started");
 	string name=string("v");
 	v=variableType::getOrCreateVar(name, T_INTVAR);
-	v->assignment(new expression(new constOp("2", T_INT)));
+	logger("variable v created");
+	o=new constOp("2", T_INT);
+	logger("constOp 2 created");
+	v->assignment(new expression(o));
+	logger("assignment created");
 	print=new printSegment(new expression(v));
 	print->generate();
 	delete print;
+	logger("testInt cleared.");
 }
 
 void testString()
 {
+	logger("testString started");
 	string name=string("name1");
 	v=variableType::getOrCreateVar(name, T_STRINGVAR);
 	v->assignment(new expression(new constOp("Hello", T_STRING)));
@@ -297,10 +308,12 @@ void testString()
 	print=new printSegment(new expression(new constOp(" world!", T_STRING)));
 	print->generate();
 	delete print;
+	logger("testString cleared");
 }
 
 void testFloat()
 {
+	logger("testFloat started");
 	string name=string("floater");
 	v=variableType::getOrCreateVar(name, T_FLOATVAR);
 	v->assignment(new expression(new constOp("3.14159265", T_FLOAT)));
@@ -310,6 +323,40 @@ void testFloat()
 	print=new printSegment(new expression(new constOp(" is pi", T_STRING)));
 	print->generate();
 	delete print;
+	logger("testFloat cleared");
+}
+
+void testFunc()
+{
+	logger("testFunc started");
+	string name=string("square");
+	logger("aloha");
+	o = operands::createOp(T_FLOATVAR);
+	logger("mahalo");
+	func=fn::declare(name, T_FLOATFUNC, o);
+	logger("funkBeat");
+	name=string("radius");
+	v=variableType::getOrCreateVar(name, T_FLOATVAR);
+	logger("param made");
+	func->addParameter(v);
+	logger("param added");
+	e=new expression(new expression(v), O_MULTIPLY, new expression(v));
+	logger("expression made");
+	func->generateReturn(e);
+	logger("return generated");
+	func->close();
+	logger("function ended");
+	o=new constOp("3.0", T_FLOAT);
+	p.push_back(o);
+	name=string("square");
+	o=func->generateCall(name, p);
+	logger("call generated");
+	e=new expression(o);
+	print=new printSegment(e);
+	o->dispose();
+	print->generate();
+	delete print;
+	logger("testFunc cleared");
 }
 
 /* open files and compile */
@@ -319,6 +366,9 @@ void compile()
 	testInt();
 	testString();
 	testFloat();
+	testFunc();
 	label::generateEnd();
+	/*check for nesting error */
+	if (!scopeGlobal) error(E_END_FUNCTION);
 	shutDown();
 }
diff --git a/yab2cpp.cpp b/yab2cpp.cpp
index 5a29d1c..b643fba 100644
--- a/yab2cpp.cpp
+++ b/yab2cpp.cpp
@@ -71,6 +71,7 @@ const string CODETYPES[]={
 enum COMPILE_ERRORS errorLevel=E_OK;
 unsigned int indentLevel=0;
 bool scopeGlobal=true;
+unsigned int currentFunc=0;
 
 bool COMPILE=false;
 bool DUMP=false;
@@ -247,8 +248,6 @@ void shutDown()
 		<< COMPILE_ERROR_NAMES[errorLevel] << "\n\n" << endl;
 	logger("Purging tempVar queues");
 	tempVar::eraseQueues();
-	logger("Dumping stack.");
-	if (DUMP && (logfile)) fn::dumpCallStack();
 	if (DUMP)
 	{
 		varNames << "Global Variables\n";
diff --git a/yab2cpp.h b/yab2cpp.h
index 7f06902..8ce4c84 100644
--- a/yab2cpp.h
+++ b/yab2cpp.h
@@ -60,7 +60,9 @@ enum COMPILE_ERRORS:unsigned int
 
 extern enum COMPILE_ERRORS errorLevel;
 extern unsigned int indentLevel;
+/*TODO: Replace scopeGlobal with currentFunc==0*/
 extern bool scopeGlobal;
+extern unsigned int currentFunc;
 
 /* flags used internally by the compiler */
 extern bool COMPILE;
@@ -134,6 +136,7 @@ enum SCOPES:unsigned int
 
 enum OPERATORS:unsigned int
 {
+	O_NOP,
 	O_PLUS,
 	O_MINUS,
 	O_MULTIPLY,
@@ -247,8 +250,7 @@ public:
 
 	/* Terminal expression node */
 	expression(operands *x);
-	virtual ~expression()
-	{}
+	virtual ~expression();
 };
 
 /* parent class of all code types */
@@ -357,12 +359,14 @@ public:
 class variableType:public operands
 {
 	enum SCOPES myScope;
+	unsigned int localID;
 public:
 	static variableType *getOrCreateVar(string &name, enum TYPES t);
 
+	virtual string boxName();
 	void assignment(expression *value);
 	/* always call generateBox() after new variableType() */
-	variableType(enum SCOPES s, string &name, enum TYPES t);
+	variableType(enum SCOPES s, string &name, enum TYPES t, unsigned int fnID);
 	variableType();
 	~variableType()
 	{}
@@ -400,42 +404,43 @@ public:
 	virtual ~forLoop();
 };
 
-class fn:codeType
+class fn
 {
 	static unordered_map<string, unique_ptr<fn> > functions;
-	static list<fn *> callStack;
 	static unsigned int nextID;
 	list<variableType * >params;
-	string funcName;
 	unsigned int id;
+	enum CODES type;
 	enum TYPES kind;
 	operands *rc;
 	/* two labels common to all subroutine calls */
 	label *startAddr;
-	label *ret;
-	/* private constructor used by generateGosub and generateOnNSub*/
-	fn(label *gosub);
+	/* stamdard constructor called by declare */
+	fn(enum CODES t, operands *returnCode=nullptr);
 public:
-	static void dumpCallStack();
-	static fn *getCurrentSub();
 	static fn *getSub(string &name);
 	static void generateGosub(label * sub);
 	/* must be called after label::generateOnNSkip */
 	static void generateOnNSub(expression *e, unsigned int skip);
 
+	enum CODES getType() const {return this->type;}
 	unsigned int getID() const {return this->id;}
-	int getNumParams() const {return this->params.size();}
+	size_t getNumParams() const {return this->params.size();}
 	void addParameter(variableType *);
 
 	operands *generateCall(string &name, list<operands *>&paramList);
+	/* standard return is for call */
 	void generateReturn(expression *expr);
+	/* parameterless return is for gosub */
 	void generateReturn();
 	virtual void generateBreak();
 	virtual void close();
 
-	fn(string &name, enum CODES t, operands *returnCode=nullptr);
-	virtual ~fn()
-	{}
+	static fn *declare(string &name, enum CODES t, operands *returnCode=nullptr);
+	static void dumpFunctionIDs();
+
+	/* is called only by unique_ptr in static "functions" hash table */
+	virtual ~fn();
 };
 
 class printSegment
diff --git a/yabDataStructures.cpp b/yabDataStructures.cpp
index 61da7b9..125466d 100644
--- a/yabDataStructures.cpp
+++ b/yabDataStructures.cpp
@@ -35,7 +35,7 @@ enum TYPES operands::getSimpleVarType(enum TYPES t)
 		case T_STRINGVAR:
 			return T_STRINGVAR;
 		default:
-		break;
+			break;
 	}
 	error(E_UNASSIGNABLE_TYPE);
 }
@@ -87,19 +87,18 @@ void operands::generateBox(enum SCOPES s)
 
 operands *operands::createOp(enum TYPES t)
 {
-	if (DEBUG)
+	if (TRACE)
 	{
-		operands *x=createOp(t);
-		x->generateBox(scopeGlobal?S_GLOBAL:S_LOCAL);
-		return x;
+		indent();
+		logfile << "Creating operand of type "
+			<< TYPENAMES[t] << endl;
 	}
 	return tempVar::getOrCreateVar(t);
 }
 
+/* only tempVar type needs disposing */
 void operands::dispose()
-{
-	delete this;
-}
+{}
 
 string operands::boxName()
 {
@@ -295,8 +294,8 @@ expression::expression(expression *l, enum OPERATORS o, expression *r)
 
 expression::expression(operands *x)
 {
-	op=x;
-	oper=O_TERM;
+	this->op=x;
+	this->oper=O_TERM;
 }
 
 /* binary vs. unary ops */
@@ -323,10 +322,14 @@ operands *expression::evaluate()
 	operands *l;
 	operands *r;
 	enum TYPES t;
+	logger("evaluating left");
 	l=this->getLeft()->evaluate();
+	logger("left evaluated");
 	if (this->isBinOp())
 	{
+		logger("evaluating right");
 		r=this->getRight()->evaluate();
+		logger("evaluated right");
 		enum TYPES lt=l->getSimpleVarType();
 		enum TYPES rt=r->getSimpleVarType();
 		if (lt==T_INTVAR && rt==T_FLOATVAR)
@@ -398,6 +401,7 @@ operands *expression::evaluate()
 		this->op=operands::createOp(t);
 		output_cpp << this->op->boxName() << "=" << l->boxName()
 			<< "*" << r->boxName() << ";\n";
+		logger("multiply done");
 		break;
 	case O_OR:
 		if (t!=T_INTVAR) error(E_TYPE_MISMATCH);
@@ -445,21 +449,32 @@ operands *expression::evaluate()
 		error(E_INTERNAL);
 	}
 	/* convert expression into single operand */
-	this->oper=O_TERM;
-	l->dispose();
+	logger("deleting left");
 	delete left;
-	if (getRight()!=nullptr)
+	logger("left deleted");
+	if (isBinOp())
 	{
-		r->dispose();
+		logger("deleting right");
 		delete right;
+		logger("right deleted");
 	}
+	this->oper=O_TERM;
 	return this->op;
 }
 
+expression::~expression()
+{
+	if(this->getOp()==O_TERM)
+	{
+		op->dispose();
+	}
+}
+
 /* variable definitions */
-variableType::variableType(enum SCOPES s, string &name, enum TYPES t):operands(t)
+variableType::variableType(enum SCOPES s, string &name, enum TYPES t, unsigned int fnID):operands(t)
 {
 	this->myScope=s;
+	this->localID=fnID;
 	switch (s)
 	{
 		case S_LOCAL:
@@ -481,6 +496,18 @@ variableType::variableType(enum SCOPES s, string &name, enum TYPES t):operands(t
 	}
 }
 
+string variableType::boxName()
+{
+	ostringstream ss;
+	if (myScope==S_LOCAL)
+	{
+		ss << "sub" << this->localID << "->v" << this->getID();
+		return ss.str();
+	}
+	ss << "v" << this->getID();
+	return ss.str();
+}
+
 variableType *variableType::getOrCreateVar(string &name, enum TYPES t)
 {
 	if (!scopeGlobal)
@@ -491,7 +518,15 @@ variableType *variableType::getOrCreateVar(string &name, enum TYPES t)
 		if(i!=statics.end())return i->second.get();
 	}
 	if (globals.find(name)!=globals.end())return globals[name].get();
-	variableType *v=new variableType(scopeGlobal?S_GLOBAL:S_LOCAL, name, t);
+	variableType *v;
+	if (scopeGlobal)
+	{
+		v=new variableType(S_GLOBAL, name, t, 0);
+	}
+	else
+	{
+		v=new variableType(S_LOCAL, name, t, currentFunc);
+	}
 	v->generateBox(scopeGlobal?S_GLOBAL:S_LOCAL);
 	return v;
 }
@@ -522,7 +557,6 @@ void variableType::assignment(expression *value)
 				<< op->boxName() << ";\n";
 			break;
 	}
-	op->dispose();
 	delete value;
 }
 
@@ -566,7 +600,7 @@ string arrayType::generateBox(enum SCOPES s)
 }
 
 arrayType::arrayType(string &name, enum TYPES t, list<unsigned int>dim):
-	variableType(S_GLOBAL, name, t)
+	variableType(S_GLOBAL, name, t, 0)
 {
 	this->dimensions=dim;
 }
diff --git a/yabFunctions.cpp b/yabFunctions.cpp
index 8269fe7..734a619 100644
--- a/yabFunctions.cpp
+++ b/yabFunctions.cpp
@@ -10,35 +10,30 @@
 
 /* static initializers */
 unordered_map<string, unique_ptr<fn> > fn::functions;
-list<fn *>fn::callStack;
-unsigned int fn::nextID=0;
+unsigned int fn::nextID;
 
 /* function definitions */
-void fn::dumpCallStack()
+void fn::dumpFunctionIDs()
 {
-	auto i=callStack.rbegin();
-	if (i==callStack.rend())
+	varNames << "Function IDs\n";
+	auto i=functions.begin();
+	if (i==functions.end())
 	{
-		logfile << "call stack was empty\n";
+		varNames << "no named functions\n";
 		return;
 	}
 	do
 	{
-		logfile << (*i)->funcName << "\n";
+		varNames << "Function " << i->first
+			<< " has ID f" << i->second.get()->getID() << "\n";
 		++i;
-	} while(i!=callStack.rend());
-}
-
-fn *fn::getCurrentSub()
-{
-	return callStack.back();
+	} while (i!=functions.end());
 }
 
 void fn::generateOnNSub(expression *e, unsigned int skip)
 {
 	label *r=new label();
-	fn *self=new fn(r);
-	fn::callStack.push_back(self);
+	output_cpp << "callStack=new subroutine(" << r->getID() << ");\n";
 	label::generateOnNTo(e, skip);
 	r->generate();
 }
@@ -46,18 +41,11 @@ void fn::generateOnNSub(expression *e, unsigned int skip)
 void fn::generateGosub(label *sub)
 {
 	label *r=new label();
-	fn *self=new fn(r);
-	fn::callStack.push_back(self);
+	output_cpp << "callStack=new subroutine(" << r->getID() << ");\n";
 	sub->generateJumpTo();
 	r->generate();
 }
 
-fn::fn(label *gosub):codeType(T_GOSUB)
-{
-	this->funcName="unnamed gosub";
-	this->ret=gosub;
-}
-
 fn *fn::getSub(string &name)
 {
 	auto iter=fn::functions.find(name);
@@ -65,32 +53,42 @@ fn *fn::getSub(string &name)
 	return iter->second.get();
 }
 
+void fn::addParameter(variableType *v)
+{
+	this->params.push_back(v);
+}
+
+/* TODO needs to be broken into smaller pieces */
 operands *fn::generateCall(string &name, list<operands *>&paramList)
 {
 	auto v=params.begin();
 	operands *current;
+	label *retAddr=new label();
 	fn *g=fn::getSub(name);
 	if (g==nullptr)
 	{
 		error(E_SUBROUTINE_NOT_FOUND);
 	}
-	if (paramList.size()>params.size())
+	if (paramList.size() > this->getNumParams())
 	{
 		error(E_TOO_MANY_PARAMETERS);
 	}
 	/* TODO CHECK THIS */
 	output_cpp << "struct f" << g->getID()
-		<< "*sub" << this->getID()
+		<< " *sub" << this->getID()
 		<< "= new struct f" << g->getID()
-		<< "();\n";
+		<< "(" << retAddr->getID() << ");\n"
+		<< "callStack = sub" <<this->getID() << ";\n";
 
 	/* TODO Make parameter processing a separate function */
 	while(paramList.size()>0)
 	{
-		current= paramList.front();
+		current=paramList.front();
 		paramList.pop_front();
 		if(current->getSimpleVarType()!=(*v)->getType())
 		{
+			cerr << "assigning " << TYPENAMES[current->getType()]
+				<< " to " << (*v)->getType() << endl;
 			error(E_TYPE_MISMATCH);
 		}
 		(*v)->assignment(new expression(current));
@@ -115,53 +113,44 @@ operands *fn::generateCall(string &name, list<operands *>&paramList)
 		++v;
 	}
 	g->startAddr->generateJumpTo();
-	g->ret->generate();
+	retAddr->generate();
 	return g->rc;
 }
 
+/* typeless return for gosub family */
 void fn::generateReturn()
 {
-	fn *c=getCurrentSub();
-	switch(c->getType())
-	{
-		case T_UNKNOWNFUNC:
-			/* set return type to NONE */
-			this->kind=T_NONE;
-			/*fallthrough*/
-		case T_GOSUB:
-			c->ret->generateJumpTo();
-			fn::callStack.pop_back();
-			break;
-		default:
-			error(E_TYPE_MISMATCH);
-	}
+	output_cpp << "state=subroutine::close();\nbreak;\n";
 }
 
 void fn::generateReturn(expression *expr)
 {
+	logger("evaluating expression");
 	this->rc=expr->evaluate();
+	logger("expression evaluated");
 	this->kind=rc->getSimpleVarType();
-	this->ret->generateJumpTo();
-	fn::callStack.pop_back();
-	delete expr;
+	logger("generating return");
+	generateReturn();
 	switch (this->getType())
 	{
 		case T_UNKNOWNFUNC:
-			return;
+			break;
 		case T_STRINGFUNC:
 			if (kind!=T_STRINGVAR) error(E_TYPE_MISMATCH);
-			return;
+			break;
 		case T_INTFUNC:
 			if (kind!=T_INTVAR&&kind!=T_FLOATVAR) error(E_TYPE_MISMATCH);
-			return;
+			break;
 		case T_FLOATFUNC:
 			if(kind!=T_FLOATVAR) error(E_TYPE_MISMATCH);
-			return;
+			break;
 		case T_GOSUB:
 			error(E_GOSUB_CANNOT_RETURN_VALUE);
 		default:
 			error(E_BAD_SYNTAX);
 	}
+	logger("deleting expression");
+	delete expr;
 }
 
 /* not allowed in function definitions directly */
@@ -181,31 +170,79 @@ void fn::close()
 		this->generateReturn();
 	}
 	funcs_h << "};\n";
+	if(DUMP)
+	{
+		auto i=locals.begin();
+		varNames << "\nLocal variables in function f" << this->getID() << "\n";
+		if(i==locals.end())
+		{
+			varNames << "no non-static locals\n";
+		}
+		else
+		{
+			do
+			{
+				varNames << "variable " << i->first	<< " has id v"
+					<< i->second.get()->getID() << "\n";
+				++i;
+			}while(i!=locals.end());
+		}
+		i=statics.begin();
+		varNames << "\n Static locals in function f" << this->getID() << "\n";
+		if (i==statics.end())
+		{
+			varNames << "no static locals\n";
+		}
+		else
+		{
+			do
+			{
+				varNames << "variable " << i->first << " has id v"
+					<< i->second.get()->getID() << "\n";
+				++i;
+			} while (i!=statics.end());
+		}
+	}
 	locals.clear();
 	statics.clear();
-	this->params.clear();
+	currentFunc=0;
 	scopeGlobal=true;
 }
 
-fn::fn(string &s, enum CODES t, operands *returnCode):codeType(t)
+fn *fn::declare(string &s, enum CODES t, operands *returnCode)
 {
 	/*check for nesting error */
 	if (!scopeGlobal) error(E_END_FUNCTION);
 	/*check if this function name is already used*/
 	if (fn::functions.find(s)!=fn::functions.end()) error(E_DUPLICATE_SYMBOL);
-	this->funcName=s;
+	logger("declaration name cleared");
+	fn *self=new fn(t, returnCode);
+	logger("fn allocated");
+	fn::functions.insert({s,unique_ptr<fn>(self)});
+	logger("fn inserted");
+	/* initiate local scope */
+	currentFunc=self->getID();
+	scopeGlobal=false;
+	return self;
+}
+
+/* standard constructor for block-formatted functions */
+fn::fn(enum CODES t, operands *returnCode)
+{
+	this->params.clear();
+	this->type=t;
 	this->id= ++nextID;
 	/*define storage for locals*/
-	funcs_h << "struct f" << this->id <<"\n{\n";
-	/*define label space for return*/
-	this->ret=new label();
-	/*allocate function name*/
-	fn::functions[s]=unique_ptr<fn>(this);
-	/* initiate local scope */
-	scopeGlobal=false;
+	if (t!=T_GOSUB) funcs_h << "struct f" << this->id <<":public subroutine\n{\n";
 	/*keep track of where the return code will be sent to*/
 	this->rc=returnCode;
 	/*allocate and generate start address label*/
 	this->startAddr=new label();
 	startAddr->generate();
 }
+
+fn::~fn()
+{
+	this->params.clear();
+	delete startAddr;
+}