diff --git a/.gitignore b/.gitignore
index 5a66296..a8ba56d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -16,5 +16,4 @@ lox-test-*
 *.lst
 
 .msc/
-test/test.lox
 
diff --git a/dub.sdl b/dub.sdl
index 90eb9b4..58a534e 100644
--- a/dub.sdl
+++ b/dub.sdl
@@ -4,19 +4,13 @@ authors "tanya"
 copyright "Copyright © 2025, tanya"
 license "MPL-2.0"
 dependency "commandr" version="~>1.1.0"
-dependency "colored" version="~>0.0.33"
+dependency "taggedalgebraic" version="~>0.11.23"
 targetType "executable"
-sourcePaths
-configuration "clox" {
-	/* debugVersions "traceExec" */
-	debugVersions "printCode"
-	targetType "executable"
-	sourcePaths "src/clox" "src/common"
-	buildRequirements "requireBoundsCheck" "requireContracts"
-}
+buildRequirements "requireBoundsCheck" "requireContracts"
+
+versions "LoxConcatNonStrings" "LoxExtraNativeFuncs"
+
 configuration "jlox" {
-	targetType "executable"
 	sourcePaths "src/jlox" "src/common"
-	versions "LoxConcatNonStrings" "LoxExtraNativeFuncs" "LoxPrintMultiple"
-	buildRequirements "requireBoundsCheck" "requireContracts"
 }
+
diff --git a/dub.selections.json b/dub.selections.json
index ead0009..6b90314 100644
--- a/dub.selections.json
+++ b/dub.selections.json
@@ -1,9 +1,7 @@
 {
 	"fileVersion": 1,
 	"versions": {
-		"colored": "0.0.33",
 		"commandr": "1.1.0",
-		"taggedalgebraic": "0.11.23",
-		"unit-threaded": "2.2.3"
+		"taggedalgebraic": "0.11.23"
 	}
 }
diff --git a/src/clox/chunk.d b/src/clox/chunk.d
deleted file mode 100644
index e41bcaf..0000000
--- a/src/clox/chunk.d
+++ /dev/null
@@ -1,69 +0,0 @@
-module clox.chunk;
-
-import std.container.array;
-import std.stdio;
-import std.algorithm.searching;
-
-import clox.value;
-import clox.container.rle;
-import clox.container.int24;
-
-enum SimpleOp;
-enum LogicOp;
-enum ValueOp;
-enum ArithOp;
-enum CompOp;
-enum OpCode : ubyte{
-	Constant,
-	@ValueOp Nil,
-	@ValueOp True,
-	@ValueOp False,
-
-	@(SimpleOp, CompOp) Equal,
-	@(SimpleOp, CompOp) Greater,
-	@(SimpleOp, CompOp) Less,
-	@(SimpleOp, CompOp) NotEqual,
-	@(SimpleOp, CompOp) GreaterEqual,
-	@(SimpleOp, CompOp) LessEqual,
-
-	@(SimpleOp, ArithOp) Add,
-	@(SimpleOp, ArithOp) Subtract,
-	@(SimpleOp, ArithOp) Multiply,
-	@(SimpleOp, ArithOp) Divide,
-
-	@(SimpleOp, LogicOp) Not,
-	@(SimpleOp, LogicOp) Negate,
-	@(SimpleOp) Return,
-}
-import std.traits: hasUDA;
-bool isSimpleOp(alias op)() => hasUDA!(op, SimpleOp);
-bool isValueOp(alias op)() => hasUDA!(op, ValueOp);
-bool isLogicOp(alias op)() => hasUDA!(op, LogicOp);
-bool isCompOp(alias op)() => hasUDA!(op, CompOp);
-bool isArithOp(alias op)() => hasUDA!(op, ArithOp);
-bool isSize1Op(alias op)() => isSimpleOp!op || isValueOp!op;
-static assert( isSimpleOp!(OpCode.Equal) );
-static assert( !isSimpleOp!(OpCode.Constant) );
-
-struct Chunk{
-	Array!ubyte code;
-	Rle!(Uint24, ubyte) lines;
-	Array!Value constants;
-	uint addConstant(in Value value) @nogc nothrow {
-		long index = constants[].countUntil(value);
-		if(index >= 0)
-			return cast(uint)index;
-		constants ~= value;
-		return cast(uint)((constants.length) - 1);
-	}
-	void write(ubyte b, uint line = 0) @nogc nothrow {
-		ubyte[1] data = [ b ];
-		write(data, line);
-	}
-	void write(ubyte[] b, uint line = 0) @nogc nothrow {
-		code ~= b;
-		foreach(i; 0 .. b.length)
-			lines ~= Uint24(line); // TODO could be done without a loop
-	}
-}
-
diff --git a/src/clox/compiler.d b/src/clox/compiler.d
deleted file mode 100644
index 1107ca5..0000000
--- a/src/clox/compiler.d
+++ /dev/null
@@ -1,30 +0,0 @@
-module clox.compiler;
-
-import std.stdio;
-
-import clox.scanner, clox.parser, clox.emitter;
-import clox.chunk;
-import clox.value;
-import clox.util;
-import clox.parserules;
-import clox.dbg;
-
-struct Compiler{
-	Scanner scanner;
-	Parser parser;
-	Emitter emitter;
-	bool compile(string source, Chunk* chunk){
-		scanner = Scanner(source);
-		parser = Parser(&this);
-		emitter = Emitter(&this, chunk);
-
-		parser.advance();
-		parser.expression();
-		parser.consume(Token.Type.EOF, "Expect end of expression.");
-		debug writeln(*chunk);
-		emitter.endCompiler();
-		return !parser.hadError;
-	}
-}
-
-
diff --git a/src/clox/container/int24.d b/src/clox/container/int24.d
deleted file mode 100644
index 406a933..0000000
--- a/src/clox/container/int24.d
+++ /dev/null
@@ -1,26 +0,0 @@
-module clox.container.int24;
-
-struct Uint24{
-	nothrow: @nogc: @safe:
-	ubyte[3] data;
-	static Uint24 opCall(uint n){
-		import std.bitmanip : nativeToLittleEndian;
-		Uint24 u3;
-		assert(n <= 16_777_215);
-		ubyte[uint.sizeof] d = nativeToLittleEndian!uint(n);
-		u3.data[0 .. 3] = d[0 .. 3];
-		return u3;
-	}
-}
-uint toUint(Uint24 u3) @nogc nothrow @safe {
-	import std.bitmanip : littleEndianToNative;
-	ubyte[4] temp;
-	temp[0 .. 3] = u3.data;
-	return littleEndianToNative!uint(temp);
-}
-unittest{
-	static assert(Uint24.sizeof == 3);
-	assert(Uint24(5).toUint == 5);
-	assert(Uint24(16_777_215).toUint == 16_777_215);
-}
-
diff --git a/src/clox/container/rle.d b/src/clox/container/rle.d
deleted file mode 100644
index f6e117a..0000000
--- a/src/clox/container/rle.d
+++ /dev/null
@@ -1,62 +0,0 @@
-module clox.container.rle;
-
-import std.traits;
-import std.container.array;
-
-struct Rle(T, L = ubyte) if(isUnsigned!L){
-	nothrow: @nogc:
-	align(1) struct Count{
-		T item;
-		L num;
-	}
-	size_t total;
-	Array!Count data;
-	private void pushNew(T item){
-		data ~= Count(item, 0);
-	}
-	size_t push(T item){
-		if(data.length){
-			Count* d = &data[(data.length)-1];
-			if(d.item == item && d.num < L.max){
-				d.num++;
-				return total++;
-			}
-		}
-		pushNew(item);
-		return total++;
-	}
-	T opOpAssign(string op: "~")(T rhs){
-		push(rhs);
-		return rhs;
-	}
-	T opIndex(size_t n) const @safe{
-		assert(n < total);
-		size_t c;
-		for(size_t i; i < n;){
-			i += data[c].num + 1;
-			if(i <= n)
-				c++;
-		}
-		return data[c].item;
-	}
-}
-unittest{
-	import clox.container.int24;
-	auto rl = Rle!(Uint24, ubyte)();
-	static assert(rl.Count.sizeof == 4);
-	foreach(i; 0..300){
-		size_t index = rl.push(Uint24(5));
-		assert(rl[index].toUint == 5);
-	}
-	assert(rl[299].toUint == 5);
-	foreach(i; 0..30){
-		size_t index = rl.push(Uint24(0));
-		assert(rl[index].toUint == 0);
-	}
-	assert(rl[0].toUint == 5);
-	foreach(i; 0..300){
-		size_t index = rl.push(Uint24(16_777_215));
-		assert(rl[index].toUint == 16_777_215);
-	}
-}
-
diff --git a/src/clox/container/stack.d b/src/clox/container/stack.d
deleted file mode 100644
index 9dabed1..0000000
--- a/src/clox/container/stack.d
+++ /dev/null
@@ -1,26 +0,0 @@
-module clox.container.stack;
-
-struct Stack(T, size_t N){
-	@nogc: nothrow:
-	T* top;
-	T[N] data;
-	invariant{ assert(top <= data.ptr + N); assert(top >= data.ptr); }
-	this(int _) @safe{
-		top = data.ptr;
-	}
-	void push(T value){
-		assert(top < data.ptr + N);
-		debug assert(*top is T.init);
-		*(top++) = value;
-	}
-	T pop(){
-		assert(top > data.ptr);
-		T t = *(--top);
-		debug *(top) = T.init;
-		return t;
-	}
-	const(T)[] live() const @safe{
-		return data[0 .. (top - data.ptr)];
-	}
-}
-
diff --git a/src/clox/container/varint.d b/src/clox/container/varint.d
deleted file mode 100644
index d1d467b..0000000
--- a/src/clox/container/varint.d
+++ /dev/null
@@ -1,73 +0,0 @@
-module clox.container.varint;
-
-struct VarUint{
-	import std.bitmanip;
-	nothrow: @nogc:
-	uint i;
-	ubyte len;
-	ubyte[4] data;
-	this(long l) @safe {
-		if(l < 0b1000_0000){
-			len = 1;
-			data[0] = (cast(ubyte)l);
-			return;
-		}
-		if(l < 0b0100_0000__0000_0000){
-			len = 2;
-			data[0 .. 2] = nativeToBigEndian(cast(ushort)l);
-			data[0] |= 0b1000_0000;
-			return;
-		}
-		if(l < 0b0010_0000__0000_0000__0000_0000__0000_0000){
-			len = 4;
-			data[0 .. 4] = nativeToBigEndian(cast(uint)l);
-			data[0] |= 0b1100_0000;
-			return;
-		}
-		assert(0);
-	}
-	static VarUint read(const(ubyte)[] data) @safe {
-		VarUint v;
-		ubyte a = data[0];
-		if((data[0] & 0b1000_0000) == 0){
-			v.i = a;
-			v.len = 1;
-			return v;
-		}
-		if((a & 0b0100_0000) == 0){
-			ubyte[2] d = data[0 .. 2];
-			d[0] &= 0b0111_1111;
-			v.i = bigEndianToNative!ushort(d);
-			v.len = 2;
-			return v;
-		}
-		if((a & 0b0010_0000) == 0){
-			ubyte[4] d = data[0 .. 4];
-			d[0] &= 0b0011_1111;
-			v.i = bigEndianToNative!uint(d);
-			v.len = 4;
-			return v;
-		}
-		assert(0);
-	}
-	ubyte[] bytes() @nogc nothrow {
-		return data[0 .. len];
-	}
-}
-unittest{
-	import std.range;
-	assert(VarUint(5).bytes.length == 1);
-	assert(VarUint(127).bytes.length == 1);
-	assert(VarUint(128).bytes.length == 2);
-	assert(VarUint(536_870_911).bytes.length == 4);
-	foreach(ulong i; [
-		0, 1, 2, 5,
-		150, 127, 128,
-		536_870_911,
-		ushort.max * 100
-	]){
-		auto vi = VarUint(i);
-		assert(i == VarUint.read(vi.bytes).i);
-	}
-}
-
diff --git a/src/clox/container/vartype.d b/src/clox/container/vartype.d
deleted file mode 100644
index 1a27cc9..0000000
--- a/src/clox/container/vartype.d
+++ /dev/null
@@ -1,59 +0,0 @@
-module clox.container.vartype;
-
-import std.stdio;
-import std.algorithm;
-import std.array;
-import std.uni;
-import std.conv;
-
-struct VarType(S) if(is(S == union)){
-	private enum members = __traits(derivedMembers, S);
-	mixin("enum Type{ None, ", [members].map!asCapitalized.join(", "), "}");
-	private S value;
-	private Type _type;
-	Type type() const @safe @nogc nothrow => _type;
-	private void check(Type t) const @safe nothrow @nogc{
-		assert(this.type == t, "Tried to get wrong type");
-	}
-	private template funcs(string G, string T){
-		mixin("bool is", G, "() const nothrow @nogc @safe => this.type == this.Type.", G, ";");
-		mixin("auto get", G, "() const nothrow @nogc { check(this.Type.", G, "); return value.", T, "; }");
-		mixin("void set", G, "(typeof(S.", T, ") v = typeof(S.", T, ").init){ this._type = this.Type.", G, "; this.value.", T, " = v; }");
-		mixin("static auto ", T, "(typeof(S.", T, ") v){ typeof(this) vt; vt.set", G, "(v); return vt; }");
-		mixin("static auto ", T, "(){ typeof(this) vt; vt.set", G, "(); return vt; }");
-	}
-	static foreach(s; members){
-		mixin funcs!(s.asCapitalized.to!string, s);
-	}
-	string toString() const{
-		final switch(_type){
-			static foreach(s; members){
-				mixin("case Type.", s.asCapitalized.to!string, ": return _type.to!string ~ ':' ~ get", s.asCapitalized.to!string, ".to!string ;");
-			}
-			case Type.None: return "None";
-		}
-	}
-}
-
-unittest{
-	import std.exception, std.stdio;
-	union Test{
-		uint u;
-		int i;
-		double d;
-	}
-	auto i = VarType!Test.i(-5);
-	assert(i.getI == -5);
-	assert(i.type == i.Type.I);
-	assert(i.isI);
-	assert(!i.isD);
-	i.setD(0.5);
-	assert(i.getD == 0.5);
-	assert(i.type == i.Type.D);
-	assert(i.isD);
-	assert(!i.isU);
-
-	auto i2 = VarType!Test.i();
-	assert(i2.isI);
-}
-
diff --git a/src/clox/dbg.d b/src/clox/dbg.d
deleted file mode 100644
index 570efc5..0000000
--- a/src/clox/dbg.d
+++ /dev/null
@@ -1,66 +0,0 @@
-module clox.dbg;
-
-import std.stdio;
-import std.conv;
-import std.uni;
-import std.format;
-
-import colored;
-
-import clox.chunk;
-import clox.value;
-import clox.util;
-import clox.container.varint;
-import clox.container.int24;
-
-private ulong simpleInstruction(alias op)(string name, ulong offset){
-	static if(isValueOp!op)
-		writeln(name.cyan);
-	else static if(isLogicOp!op)
-		writeln(name.lightRed);
-	else static if(isCompOp!op)
-		writeln(name.red);
-	else static if(isArithOp!op)
-		writeln(name.yellow);
-	else
-		writeln(name.lightCyan);
-	return offset + 1;
-}
-private ulong constantInstruction(string name, Chunk* chunk, ulong offset){
-	/* ubyte constant = chunk.code[offset + 1]; */
-	VarUint constant = VarUint.read(chunk.code.data[offset + 1 .. $]);
-	/* writeln(constant); */
-	write("%-16s".format(name).cyan, " %4d ".format(constant.i).lightMagenta, "'");
-	printValue(chunk.constants[constant.i]);
-	writeln("'");
-	return offset + 1 + constant.len;
-}
-
-void disassembleChunk(Chunk* chunk, string name = "chunk"){
-	writefln("== %s ==", name);
-	for(ulong offset = 0; offset < chunk.code.length;)
-		offset = disassembleInstruction(chunk, offset);
-}
-ulong disassembleInstruction(Chunk* chunk, const ulong offset){
-	write(" %04d ".format(offset).lightGray);
-	if(offset > 0 && chunk.lines[offset] == chunk.lines[offset - 1]){
-		write("    | ".darkGray);
-	} else {
-		write(" %4d ".format(chunk.lines[offset].toUint).lightGray);
-	}
-	ubyte instruction = chunk.code[offset];
-	with(OpCode) switch(instruction){
-		import std.meta, std.traits;
-		case Constant:
-			return constantInstruction("OP_CONSTANT", chunk, offset);
-		static foreach(k; Filter!(isSize1Op, EnumMembers!OpCode)){
-			case k:
-				static name = "OP_" ~ (k.to!string).toUpper;
-				return simpleInstruction!k(name, offset);
-		}
-		default:
-			writefln("Unknown opcode %d", instruction);
-			return offset + 1;
-	}
-}
-
diff --git a/src/clox/emitter.d b/src/clox/emitter.d
deleted file mode 100644
index 116f504..0000000
--- a/src/clox/emitter.d
+++ /dev/null
@@ -1,51 +0,0 @@
-module clox.emitter;
-
-import clox.compiler;
-import clox.chunk;
-import clox.value;
-import clox.util;
-import clox.dbg;
-
-import clox.container.varint;
-
-struct Emitter{
-	Compiler* compiler;
-	Chunk* chunk;
-	private uint line = 1;
-	Chunk* currentChunk(){
-		return chunk;
-	}
-	void emit(Args...)(Args args){
-		static foreach(v; args){{
-			static if(is(typeof(v) == OpCode)){
-				auto bytes = v;
-			} else static if(is(typeof(v) == uint)){
-				auto bytes = VarUint(v).bytes;
-			} else {
-				static assert(0);
-			}
-			currentChunk.write(bytes, line);
-		}}
-	}
-	void emitConstant(Value value){
-		emit(OpCode.Constant, makeConstant(value));
-	}
-	void emitReturn(){
-		emit(OpCode.Return);
-	}
-	void endCompiler(){
-		emitReturn();
-		debug(printCode){
-			if(!compiler.parser.hadError)
-				disassembleChunk(currentChunk());
-		}
-	}
-	uint makeConstant(Value value){
-		uint constant = chunk.addConstant(value);
-		return constant;
-	}
-	void setLine(uint l){
-		this.line = l;
-	}
-}
-
diff --git a/src/clox/main.d b/src/clox/main.d
deleted file mode 100644
index 19e0fe7..0000000
--- a/src/clox/main.d
+++ /dev/null
@@ -1,46 +0,0 @@
-module clox.main;
-
-import std.stdio;
-import std.file;
-
-import clox.chunk;
-import clox.dbg;
-import clox.vm;
-
-extern(C) int isatty(int);
-
-struct Lox{
-	VM vm;
-	this(int _){
-		vm = VM(0);
-	}
-	int runFile(string path){
-		string source = path.readText();
-		VM.InterpretResult result = vm.interpret(source);
-		final switch(result){
-			case VM.InterpretResult.CompileError: return 65;
-			case VM.InterpretResult.RuntimeError: return 70;
-			case VM.InterpretResult.Ok: return 0;
-		}
-	}
-	int runPrompt(){
-		while(true){
-			write("lox> ");
-			string line = stdin.readln();
-			if(!line){
-				writeln();
-				return 0;
-			}
-			vm.interpret(line);
-		}
-	}
-}
-
-int main(string[] argv){
-	Lox lox = Lox(0);
-	if(isatty(stdin.fileno))
-		return lox.runPrompt();
-	else
-		return lox.runFile("/dev/stdin");
-}
-
diff --git a/src/clox/parser.d b/src/clox/parser.d
deleted file mode 100644
index 24bbdbd..0000000
--- a/src/clox/parser.d
+++ /dev/null
@@ -1,66 +0,0 @@
-module clox.parser;
-
-import clox.compiler;
-import clox.value;
-import clox.scanner;
-import clox.parserules;
-
-struct Parser{
-	Compiler* compiler;
-	Token current, previous;
-	bool hadError, panicMode;
-	void errorAtCurrent(string message){
-		errorAt(current, message);
-	}
-	void error(string message){
-		errorAt(previous, message);
-	}
-	void errorAt(in ref Token token, string message){
-		import core.stdc.stdio;
-		if(panicMode)
-			return;
-		panicMode = true;
-		fprintf(stderr, "[line %d] Error", token.line);
-		if(token.type == Token.Type.EOF){
-			fprintf(stderr, " at end");
-		} else if(token.type != Token.Type.Error){
-			fprintf(stderr, " at '%.*s'", cast(int)token.lexeme.length, token.lexeme.ptr);
-		}
-		fprintf(stderr, ": %.*s\n", cast(int)message.length, message.ptr);
-		hadError = true;
-	}
-	auto consume(Token.Type type, string msg){
-		if(current.type == type){
-			advance();
-			return;
-		}
-		errorAtCurrent(msg);
-	}
-	void advance(){
-		previous = current;
-		while(true){
-			current = compiler.scanner.scan();
-			if(current.type != Token.Type.Error)
-				break;
-			errorAtCurrent(current.lexeme);
-		}
-	}
-
-	void expression(){
-		parsePrecedence(Precedence.Assignment);
-	}
-	void parsePrecedence(Precedence precedence){
-		advance();
-		ParseFn prefixRule = ParseRule.get(previous.type).prefix;
-		if(prefixRule == null){
-			error("Expect expression.");
-			return;
-		}
-		prefixRule(compiler);
-		while(precedence <= ParseRule.get(current.type).precedence){
-			advance();
-			ParseFn infixRule = ParseRule.get(previous.type).infix;
-			infixRule(compiler);
-		}
-	}
-}
diff --git a/src/clox/parserules.d b/src/clox/parserules.d
deleted file mode 100644
index a8bff9e..0000000
--- a/src/clox/parserules.d
+++ /dev/null
@@ -1,128 +0,0 @@
-module clox.parserules;
-
-import clox.compiler;
-import clox.chunk;
-import clox.scanner;
-import clox.value;
-
-alias ParseFn = void function(Compiler* compiler);
-
-private void number(Compiler* compiler){
-	import core.stdc.stdlib : strtod;
-	Token token = compiler.parser.previous;
-	double value = strtod(token.lexeme.ptr, null);
-	compiler.emitter.setLine(token.line);
-	compiler.emitter.emitConstant(Value.num(value));
-}
-private void grouping(Compiler* compiler){
-	compiler.parser.expression();
-	compiler.parser.consume(Token.Type.RightParen, "Expect ')' after expression.");
-}
-private void unary(Compiler* compiler){
-	Token operator = compiler.parser.previous;
-	compiler.parser.parsePrecedence(Precedence.Unary);
-	compiler.emitter.setLine(operator.line);
-	switch(operator.type){
-		case Token.Type.Minus: compiler.emitter.emit(OpCode.Negate); break;
-		case Token.Type.Bang: compiler.emitter.emit(OpCode.Not); break;
-		default: assert(0);
-	}
-}
-private void binary(Compiler* compiler){
-	Token operator = compiler.parser.previous;
-	immutable(ParseRule)* rule = ParseRule.get(operator.type);
-	compiler.parser.parsePrecedence(cast(Precedence)(rule.precedence + 1));
-	compiler.emitter.setLine(operator.line);
-	switch(operator.type){
-		case Token.Type.Plus:  compiler.emitter.emit(OpCode.Add); break;
-		case Token.Type.Minus: compiler.emitter.emit(OpCode.Subtract); break;
-		case Token.Type.Star:  compiler.emitter.emit(OpCode.Multiply); break;
-		case Token.Type.Slash: compiler.emitter.emit(OpCode.Divide); break;
-
-		case Token.Type.BangEqual:  compiler.emitter.emit(OpCode.NotEqual); break;
-		case Token.Type.EqualEqual: compiler.emitter.emit(OpCode.Equal); break;
-
-		case Token.Type.Greater:  compiler.emitter.emit(OpCode.Greater); break;
-		case Token.Type.GreaterEqual: compiler.emitter.emit(OpCode.GreaterEqual); break;
-
-		case Token.Type.Less: compiler.emitter.emit(OpCode.Less); break;
-		case Token.Type.LessEqual: compiler.emitter.emit(OpCode.LessEqual); break;
-
-		default: assert(0);
-	}
-}
-private void literal(Compiler* compiler){
-	switch(compiler.parser.previous.type){
-		case Token.Type.True: compiler.emitter.emit(OpCode.True); break;
-		case Token.Type.False: compiler.emitter.emit(OpCode.False); break;
-		case Token.Type.Nil: compiler.emitter.emit(OpCode.Nil); break;
-		default: assert(0);
-	}
-}
-
-struct ParseRule{
-	ParseFn prefix;
-	ParseFn infix;
-	Precedence precedence;
-	static immutable(ParseRule)* get(Token.Type type) @nogc nothrow{
-		return &rules[type];
-	}
-}
-
-enum Precedence{
-	None,
-	Assignment,  // =
-	Or,          // or
-	And,         // and
-	Equality,    // == !=
-	Comparison,  // < > <= >=
-	Term,        // + -
-	Factor,      // * /
-	Unary,       // ! -
-	Call,        // . ()
-	Primary
-}
-
-immutable ParseRule[Token.Type.max+1] rules = [
-	Token.Type.LeftParen     : ParseRule(&grouping, null,    Precedence.None),
-	Token.Type.RightParen    : ParseRule(null,      null,    Precedence.None),
-	Token.Type.LeftBrace     : ParseRule(null,      null,    Precedence.None),
-	Token.Type.RightBrace    : ParseRule(null,      null,    Precedence.None),
-	Token.Type.Comma         : ParseRule(null,      null,    Precedence.None),
-	Token.Type.Dot           : ParseRule(null,      null,    Precedence.None),
-	Token.Type.Minus         : ParseRule(&unary,    &binary, Precedence.Term),
-	Token.Type.Plus          : ParseRule(null,      &binary, Precedence.Term),
-	Token.Type.Semicolon     : ParseRule(null,      null,    Precedence.None),
-	Token.Type.Slash         : ParseRule(null,      &binary, Precedence.Factor),
-	Token.Type.Star          : ParseRule(null,      &binary, Precedence.Factor),
-	Token.Type.Bang          : ParseRule(&unary,    null,    Precedence.None),
-	Token.Type.BangEqual     : ParseRule(null,      &binary, Precedence.Equality),
-	Token.Type.Equal         : ParseRule(null,      null,    Precedence.None),
-	Token.Type.EqualEqual    : ParseRule(null,      &binary, Precedence.Equality),
-	Token.Type.Greater       : ParseRule(null,      &binary, Precedence.Comparison),
-	Token.Type.GreaterEqual  : ParseRule(null,      &binary, Precedence.Comparison),
-	Token.Type.Less          : ParseRule(null,      &binary, Precedence.Comparison),
-	Token.Type.LessEqual     : ParseRule(null,      &binary, Precedence.Comparison),
-	Token.Type.Identifier    : ParseRule(null,      null,    Precedence.None),
-	Token.Type.String        : ParseRule(null,      null,    Precedence.None),
-	Token.Type.Number        : ParseRule(&number,   null,    Precedence.None),
-	Token.Type.And           : ParseRule(null,      null,    Precedence.None),
-	Token.Type.Class         : ParseRule(null,      null,    Precedence.None),
-	Token.Type.Else          : ParseRule(null,      null,    Precedence.None),
-	Token.Type.False         : ParseRule(&literal,  null,    Precedence.None),
-	Token.Type.For           : ParseRule(null,      null,    Precedence.None),
-	Token.Type.Fun           : ParseRule(null,      null,    Precedence.None),
-	Token.Type.If            : ParseRule(null,      null,    Precedence.None),
-	Token.Type.Nil           : ParseRule(&literal,  null,    Precedence.None),
-	Token.Type.Or            : ParseRule(null,      null,    Precedence.None),
-	Token.Type.Print         : ParseRule(null,      null,    Precedence.None),
-	Token.Type.Return        : ParseRule(null,      null,    Precedence.None),
-	Token.Type.Super         : ParseRule(null,      null,    Precedence.None),
-	Token.Type.This          : ParseRule(null,      null,    Precedence.None),
-	Token.Type.True          : ParseRule(&literal,  null,    Precedence.None),
-	Token.Type.Var           : ParseRule(null,      null,    Precedence.None),
-	Token.Type.While         : ParseRule(null,      null,    Precedence.None),
-	Token.Type.Error         : ParseRule(null,      null,    Precedence.None),
-	Token.Type.EOF           : ParseRule(null,      null,    Precedence.None),
-];
-
diff --git a/src/clox/scanner.d b/src/clox/scanner.d
deleted file mode 100644
index d916993..0000000
--- a/src/clox/scanner.d
+++ /dev/null
@@ -1,157 +0,0 @@
-module clox.scanner;
-
-import std.stdio;
-import std.ascii;
-
-import common.util;
-
-struct Token{
-	enum Type : ubyte {
-		None, Error, EOF, // Special
-		LeftParen, RightParen, // Single-character tokens.
-		LeftBrace, RightBrace,
-		Comma, Dot, Minus, Plus,
-		Semicolon, Slash, Star,
-		Bang, BangEqual, // One or two character tokens.
-		Equal, EqualEqual,
-		Greater, GreaterEqual,
-		Less, LessEqual,
-		Identifier, String, Number, // Literals.
-		And, Class, Else, False, // Keywords.
-		For, Fun, If, Nil, Or,
-		Print, Return, Super, This,
-		True, Var, While,
-	}
-	Type type;
-	int line;
-	string lexeme;
-	static Token error(string msg) nothrow @nogc => Token(Token.Type.Error, 0, msg);
-}
-
-struct Scanner{
-	nothrow:
-	@nogc:
-	string start;
-	string current;
-	int line = 1;
-	this(string source) @nogc nothrow{
-		start = current = source;
-	}
-	bool isAtEnd() const => current.length == 0;
-	private char peek() const => current[0];
-	private char peekNext() const => current.length >= 2 ? current[1] : '\0';
-	private Token makeToken(Token.Type type) const{
-		Token token;
-		token.type = type;
-		token.lexeme = start[0 .. current.ptr - start.ptr];
-		token.line = line;
-		return token;
-	}
-	private char advance(){
-		char c = current[0];
-		current = current[1 .. $];
-		return c;
-	}
-	private bool match(char needle){
-		if(isAtEnd || current[0] != needle)
-			return false;
-		current = current[1 .. $];
-		return true;
-	}
-	private void skipWhitespace(){
-		while(!isAtEnd){
-			char c = peek();
-			if(!c)
-				return;
-			if(c == '/' && peekNext() == '/'){
-				while(!isAtEnd && peek() != '\n')
-					advance();
-				continue;
-			}
-			if(!c.isWhite)
-				return;
-			/* debug writeln(c == '\n'); */
-			if(c == '\n')
-				line++;
-			current = current[1 .. $];
-		}
-	}
-	private Token parseString(){
-		while(peek() != '"' && !isAtEnd){
-			if(peek() == '\n')
-				line++;
-			advance();
-		}
-		if(isAtEnd)
-			return Token.error("Unterminated string.");
-		advance();
-		return makeToken(Token.Type.String);
-	}
-	private Token parseNumber(){
-		while(peek().isDigit)
-			advance();
-		if(peek() == '.' && peekNext().isDigit){
-			advance();
-			while(peek().isDigit)
-				advance();
-		}
-		return makeToken(Token.Type.Number);
-	}
-	private Token parseIdentifier(){
-		while(peek().isAlphaNum_)
-			advance();
-		Token token = makeToken(Token.Type.Identifier);
-		switch(token.lexeme){
-			case "and": token.type = Token.Type.And; break;
-			case "class": token.type = Token.Type.Class; break;
-			case "else": token.type = Token.Type.Else; break;
-			case "if": token.type = Token.Type.If; break;
-			case "nil": token.type = Token.Type.Nil; break;
-			case "or": token.type = Token.Type.Or; break;
-			case "print": token.type = Token.Type.Print; break;
-			case "return": token.type = Token.Type.Return; break;
-			case "super": token.type = Token.Type.Super; break;
-			case "var": token.type = Token.Type.Var; break;
-			case "while": token.type = Token.Type.While; break;
-			case "false": token.type = Token.Type.False; break;
-			case "for": token.type = Token.Type.For; break;
-			case "fun": token.type = Token.Type.Fun; break;
-			case "this": token.type = Token.Type.This; break;
-			case "true": token.type = Token.Type.True; break;
-			default: break;
-		}
-		return token;
-	}
-	Token scan(){
-		skipWhitespace();
-		start = current;
-		if(isAtEnd)
-			return Token(Token.Type.EOF);
-		char c = advance();
-		if(c.isAlpha_)
-			return parseIdentifier();
-		switch(c){
-			case '(': return makeToken(Token.Type.LeftParen);
-			case ')': return makeToken(Token.Type.RightParen);
-			case '{': return makeToken(Token.Type.LeftBrace);
-			case '}': return makeToken(Token.Type.RightBrace);
-			case ';': return makeToken(Token.Type.Semicolon);
-			case ',': return makeToken(Token.Type.Comma);
-			case '.': return makeToken(Token.Type.Dot);
-			case '-': return makeToken(Token.Type.Minus);
-			case '+': return makeToken(Token.Type.Plus);
-			case '/': return makeToken(Token.Type.Slash);
-			case '*': return makeToken(Token.Type.Star);
-			case '!': return makeToken(match('=') ? Token.Type.BangEqual : Token.Type.Bang);
-			case '=': return makeToken(match('=') ? Token.Type.EqualEqual : Token.Type.Equal);
-			case '<': return makeToken(match('=') ? Token.Type.LessEqual : Token.Type.Less);
-			case '>': return makeToken(match('=') ? Token.Type.GreaterEqual : Token.Type.Greater);
-			case '"': return parseString();
-			default: break;
-		}
-		if(c.isDigit)
-			return parseNumber();
-		return Token.error("Unexpected character.");
-	}
-}
-
diff --git a/src/clox/util.d b/src/clox/util.d
deleted file mode 100644
index 45c0945..0000000
--- a/src/clox/util.d
+++ /dev/null
@@ -1,6 +0,0 @@
-module clox.util;
-
-import std.stdio;
-import std.traits : isUnsigned;
-import std.container.array;
-
diff --git a/src/clox/value.d b/src/clox/value.d
deleted file mode 100644
index 1914616..0000000
--- a/src/clox/value.d
+++ /dev/null
@@ -1,53 +0,0 @@
-module clox.value;
-
-import std.stdio;
-
-import clox.container.vartype;
-
-/* struct Value{ */
-/* 	alias T = VarType!u; */
-/* 	private union U{ */
-/* 		bool bln; */
-/* 		bool nil; */
-/* 		double num; */
-/* 	} */
-/* 	T v; */
-/* 	alias v this; */
-/* } */
-	private union U{
-		bool bln;
-		bool nil;
-		double num;
-	}
-alias Value = VarType!U;
-
-void printValue(Value value){
-	final switch(value.type){
-		case value.Type.Bln: writef("%s", value.getBln); break;
-		case value.Type.Num: writef("%g", value.getNum); break;
-		case value.Type.Nil: writef("nil"); break;
-		case value.Type.None: assert(0);
-	}
-}
-bool isTruthy(Value value) nothrow @nogc {
-	final switch(value.type){
-		case value.Type.Bln: return value.getBln;
-		case value.Type.Num: return true;
-		case value.Type.Nil: return false;
-		case value.Type.None: assert(0);
-	}
-}
-bool isFalsey(Value value) nothrow @nogc {
-	return !isTruthy(value);
-}
-bool compare(string op)(Value a, Value b){
-	if(a.type != b.type)
-		return false;
-	final switch(a.type){
-		case a.Type.Bln: return mixin("a.getBln", op, "b.getBln");
-		case a.Type.Num: return mixin("a.getNum", op, "b.getNum");
-		case a.Type.Nil: return true;
-		case a.Type.None: assert(0);
-	}
-}
-
diff --git a/src/clox/vm.d b/src/clox/vm.d
deleted file mode 100644
index 485a626..0000000
--- a/src/clox/vm.d
+++ /dev/null
@@ -1,114 +0,0 @@
-module clox.vm;
-
-import std.stdio;
-
-import clox.chunk;
-import clox.value;
-import clox.dbg;
-import clox.util;
-import clox.compiler;
-import clox.container.stack;
-import clox.container.varint;
-import clox.container.int24;
-
-enum stackMax = 256;
-
-struct VM{
-	const(ubyte)* ip;
-	Stack!(Value, stackMax) stack;
-	Chunk* chunk;
-	enum InterpretResult{ Ok, CompileError, RuntimeError }
-	this(int _) @nogc nothrow {
-		stack = typeof(stack)(0);
-	}
-	InterpretResult interpret(string source){
-		Chunk c = Chunk();
-		Compiler compiler;
-		if(!compiler.compile(source, &c))
-			return InterpretResult.CompileError;
-		chunk = &c;
-		return interpret(chunk);
-	}
-	InterpretResult interpret(Chunk* chunk){
-		this.chunk = chunk;
-		ip = &chunk.code[0];
-		return run();
-	}
-	private void runtimeError(Args...)(string format, Args args) nothrow {
-		size_t instruction = ip - (&chunk.code[0]) - 1;
-		uint line = chunk.lines[instruction].toUint;
-		try{
-			stderr.writef("[line %d] ", line);
-			stderr.writefln(format, args);
-		} catch(Exception){}
-		/* stack.reset(); */
-	}
-	private InterpretResult run() nothrow {
-		auto readByte() => *ip++;
-		auto readIns() => cast(OpCode)readByte();
-		Value readConstant(){
-			VarUint constant = VarUint.read(ip[0 .. 4]);
-			ip += constant.len;
-			return chunk.constants[constant.i];
-		}
-		Value peek(int distance = 0){
-			return stack.top[-1 - distance];
-		}
-		while(true){
-			debug(traceExec){
-				writeln("          ", stack.live);
-				disassembleInstruction(chunk, ip - &chunk.code[0]);
-			}
-			OpCode instruction = readIns();
-			with(OpCode) opSwitch: final switch(instruction){
-				case Constant:
-					Value constant = readConstant();
-					stack.push(constant);
-					break;
-				case True:
-					stack.push(Value.bln(true));
-					break;
-				case False:
-					stack.push(Value.bln(false));
-					break;
-				case Nil:
-					stack.push(Value.nil());
-					break;
-				static foreach(k, op; [ Add: "+", Subtract: "-", Multiply: "*", Divide: "/" ]){
-					case k:
-						if(!peek(0).isNum || !peek(1).isNum){
-							runtimeError("Operands must be numbers.");
-							return InterpretResult.RuntimeError;
-						}
-						double b = stack.pop().getNum;
-						double a = stack.pop().getNum;
-						stack.push(Value.num(mixin("a", op, "b")));
-						break opSwitch;
-				}
-				static foreach(k, op; [ NotEqual: "!=", Equal: "==", Greater: ">", GreaterEqual: ">=", Less: "<", LessEqual: "<=" ]){
-					case k:
-						Value b = stack.pop();
-						Value a = stack.pop();
-						stack.push(Value.bln(compare!op(a, b)));
-						break opSwitch;
-				}
-				case Not:
-					stack.push(Value.bln(stack.pop().isFalsey));
-					break;
-				case Negate:
-					if(!peek(0).isNum){
-						runtimeError("Operand must be a number.");
-						return InterpretResult.RuntimeError;
-					}
-					stack.push(Value.num(-stack.pop().getNum));
-					break;
-				case Return:
-					debug printValue(stack.pop());
-					debug writeln();
-					return InterpretResult.Ok;
-			}
-		}
-		assert(0);
-	}
-}
-
diff --git a/src/common/util.d b/src/common/util.d
index a6876ba..14e0917 100644
--- a/src/common/util.d
+++ b/src/common/util.d
@@ -6,39 +6,3 @@ template defaultCtor(){
 			this.tupleof[i] = a;
 	}
 }
-
-import std.ascii : isAlpha, isAlphaNum;
-bool isAlpha_(dchar c)    @nogc nothrow @safe => c.isAlpha    || c == '_';
-bool isAlphaNum_(dchar c) @nogc nothrow @safe => c.isAlphaNum || c == '_';
-
-T pop(T)(ref T[] arr){
-	T v = arr.last;
-	arr.length--;
-	return v;
-}
-T shift(T)(ref T[] arr){
-	T v = arr.first;
-	arr = arr[1 .. $];
-	return v;
-}
-ref T sole(T)(T[] arr) @nogc @safe pure{
-	assert(arr.length == 1, "Not sole");
-	return arr[0];
-}
-ref T first(T)(T[] arr) @nogc @safe pure{
-	assert(arr.length >= 1, "No first");
-	return arr[0];
-}
-ref T second(T)(T[] arr) @nogc @safe pure{
-	assert(arr.length >= 2, "No second");
-	return arr[1];
-}
-ref T third(T)(T[] arr) @nogc @safe pure{
-	assert(arr.length >= 3, "No third");
-	return arr[2];
-}
-ref T last(T)(T[] arr) @nogc @safe pure{
-	assert(arr.length >= 1, "No last");
-	return arr[$-1];
-}
-
diff --git a/src/jlox/environment.d b/src/jlox/environment.d
index b1d32bd..06023dc 100644
--- a/src/jlox/environment.d
+++ b/src/jlox/environment.d
@@ -6,40 +6,26 @@ import common.util;
 
 class Environment{
 	Environment enclosing;
-	private LoxValue[string] values;
+	private TValue[string] values;
 
 	mixin defaultCtor;
 
-	void define(string name, LoxValue value){
+	void define(string name, TValue value){
 		values[name] = value;
 	}
-	LoxValue get(Token name){
-		if(LoxValue* value = name.lexeme in values)
+	TValue get(Token name){
+		if(TValue* value = name.lexeme in values)
 			return *value;
 		if(enclosing)
 			return enclosing.get(name);
 		throw new RuntimeError(name, "Undefined variable '" ~ name.lexeme ~ "'.");
 	}
-	Environment ancestor(uint distance){
-		Environment environment = this;
-		for(uint i = 0; i < distance; i++)
-			environment = environment.enclosing;
-		return environment;
-	}
-	LoxValue getAt(uint distance, string name){
-		return ancestor(distance).values[name];
-	}
-	void assign(Token name, LoxValue value){
-		if(name.lexeme in values){
-			values[name.lexeme] = value;
-			return;
-		}
+	void assign(Token name, TValue value){
+		if(name.lexeme in values)
+			return values[name.lexeme] = value;
 		if(enclosing)
 			return enclosing.assign(name, value);
 		throw new RuntimeError(name, "Undefined variable '" ~ name.lexeme ~ "'.");
 	}
-	void assignAt(uint distance, Token name, LoxValue value){
-		ancestor(distance).values[name.lexeme] = value;
-	}
 }
 
diff --git a/src/jlox/expr.d b/src/jlox/expr.d
index f95a4ff..2aea4b1 100644
--- a/src/jlox/expr.d
+++ b/src/jlox/expr.d
@@ -4,6 +4,8 @@ import std.conv;
 import std.stdio;
 import std.meta : AliasSeq;
 
+import taggedalgebraic;
+
 import jlox.token;
 import jlox.tokentype;
 import common.util;
@@ -13,17 +15,13 @@ abstract class Expr{
 		R visit(Assign expr);
 		R visit(Binary expr);
 		R visit(Call expr);
-		R visit(Get expr);
 		R visit(Grouping expr);
 		R visit(Literal expr);
 		R visit(Logical expr);
-		R visit(Set expr);
-		R visit(Super expr);
-		R visit(This expr);
 		R visit(Unary expr);
 		R visit(Variable expr);
 	}
-	private alias rTypes = AliasSeq!(string, LoxValue, void);
+	private alias rTypes = AliasSeq!(string, TValue);
 	static foreach(T; rTypes)
 		abstract T accept(Visitor!T visitor);
 	private template defCtorAndAccept(){
@@ -49,17 +47,12 @@ abstract class Expr{
 		Expr[] arguments;
 		mixin defCtorAndAccept;
 	}
-	static class Get : typeof(this){
-		Expr object;
-		Token name;
-		mixin defCtorAndAccept;
-	}
 	static class Grouping : typeof(this){
 		Expr expression;
 		mixin defCtorAndAccept;
 	}
 	static class Literal : typeof(this){
-		LoxValue value;
+		TValue value;
 		mixin defCtorAndAccept;
 	}
 	static class Logical : typeof(this){
@@ -68,21 +61,6 @@ abstract class Expr{
 		Expr right;
 		mixin defCtorAndAccept;
 	}
-	static class Set : typeof(this){
-		Expr object;
-		Token name;
-		Expr value;
-		mixin defCtorAndAccept;
-	}
-	static class Super : typeof(this){
-		Token keyword;
-		Token method;
-		mixin defCtorAndAccept;
-	}
-	static class This : typeof(this){
-		Token keyword;
-		mixin defCtorAndAccept;
-	}
 	static class Unary : typeof(this){
 		Token operator;
 		Expr right;
@@ -94,3 +72,31 @@ abstract class Expr{
 	}
 }
 
+/* class AstPrinter : Expr.Visitor!string{ */
+/* 	string print(Expr expr){ */
+/* 		return expr.accept(this); */
+/* 	} */
+/* 	string parenthesize(Args...)(string name, Args args){ */
+/* 		string s = "(" ~ name; */
+/* 		static foreach(expr; args){ */
+/* 			s ~= " "; */
+/* 			s ~= expr.accept(this); */
+/* 		} */
+/* 		return s ~ ")"; */
+/* 	} */
+/* 	string visit(Expr.Binary expr){ */
+/* 		return parenthesize(expr.operator.lexeme, expr.left, expr.right); */
+/* 	} */
+/* 	string visit(Expr.Grouping expr){ */
+/* 		return parenthesize("group", expr.expression); */
+/* 	} */
+/* 	string visit(Expr.Literal expr){ */
+/* 		if(expr.value.isNil) */
+/* 			return "nil"; */
+/* 		return expr.value.to!string; */
+/* 	} */
+/* 	string visit(Expr.Unary expr){ */
+/* 		return parenthesize(expr.operator.lexeme, expr.right); */
+/* 	} */
+/* } */
+
diff --git a/src/jlox/interpreter.d b/src/jlox/interpreter.d
index 15870bc..d248eda 100644
--- a/src/jlox/interpreter.d
+++ b/src/jlox/interpreter.d
@@ -1,7 +1,6 @@
 module jlox.interpreter;
 
 import std.conv;
-import std.exception : enforce;
 import std.stdio;
 import std.algorithm;
 import std.array;
@@ -12,12 +11,10 @@ import jlox.expr;
 import jlox.stmt;
 import jlox.token;
 import jlox.tokentype;
-import jlox.token : LoxValue;
+import jlox.token : TValue;
 import jlox.main;
 import jlox.environment;
 import jlox.loxfunction;
-import jlox.loxclass;
-import jlox.loxinstance;
 
 class RuntimeError : Exception{
 	const Token token;
@@ -27,14 +24,14 @@ class RuntimeError : Exception{
 	}
 }
 class Return : Exception{
-	const LoxValue value;
-	this(LoxValue value){
+	const TValue value;
+	this(TValue value){
 		super(null);
 		this.value = value;
 	}
 }
 
-class Interpreter : Stmt.Visitor!void, Expr.Visitor!LoxValue {
+class Interpreter : Stmt.Visitor!void, Expr.Visitor!TValue {
 	Environment globals = new Environment();
 	private Environment environment;
 	this(){
@@ -42,24 +39,20 @@ class Interpreter : Stmt.Visitor!void, Expr.Visitor!LoxValue {
 
 		import std.datetime.stopwatch;
 		auto sw = StopWatch(AutoStart.yes);
-		globals.define("clock", new class LoxCallable{
+		globals.define("clock", TValue.cal(new class LoxCallable{
 			int arity() => 0;
-			LoxValue call(Interpreter interpreter, LoxValue[] arguments) => new LoxNum(sw.peek.total!"usecs" / (1000.0 * 1000.0));
-			override string toString() const => "<native clock>";
-		});
+			TValue call(Interpreter interpreter, TValue[] arguments) => TValue.dbl(sw.peek.total!"usecs" / (1000.0 * 1000.0));
+		}));
 
 		version(LoxExtraNativeFuncs){
-			globals.define("sleep", new class LoxCallable{
+			globals.define("sleep", TValue.cal(new class LoxCallable{
 				int arity() => 1;
 				import core.thread.osthread;
-				LoxValue call(Interpreter interpreter, LoxValue[] arguments){
-					if(cast(LoxNum)arguments[0] is null)
-						throw new RuntimeError(null, "Expected number to sleep/1");
-					Thread.sleep(dur!"usecs"(cast(long)(cast(LoxNum)arguments[0] * 1000 * 1000)));
-					return new LoxNil();
+				TValue call(Interpreter interpreter, TValue[] arguments){
+					Thread.sleep(dur!"usecs"(cast(long)(arguments[0].dblValue * 1000 * 1000)));
+					return TValue.nil(tvalueNil);
 				}
-				override string toString() const => "<native sleep>";
-			});
+			}));
 		}
 	}
 	void interpret(Stmt[] statements){ 
@@ -83,59 +76,38 @@ class Interpreter : Stmt.Visitor!void, Expr.Visitor!LoxValue {
 			this.environment = previous;
 		}
 	}
-	private LoxValue evaluate(Expr expr){
+	private TValue evaluate(Expr expr){
 		return expr.accept(this);
 	}
-	private bool isTruthy(LoxValue val){
-		if(cast(LoxNil)val)
-			return false;
-		if(auto b = cast(LoxBool)val)
-			return b;
-		return true;
+	private bool isTruthy(TValue val){
+		switch(val.kind){
+			case TValue.Kind.nil:
+				return false;
+			case TValue.Kind.bln:
+				return val.blnValue;
+			default:
+				return true;
+		}
 	}
-	private bool isEqual(LoxValue a, LoxValue b){
-		return a.equals(b);
+	private bool isEqual(TValue a, TValue b){
+		return a == b;
 	}
-	private void checkNumberOperand(Token operator, LoxValue operand){
-		if(cast(LoxNum)operand)
+	private void checkNumberOperand(Token operator, TValue operand){
+		if(operand.kind == TValue.Kind.dbl)
 			return;
 		throw new RuntimeError(operator, "Operand must be a number.");
 	}
-	private uint[Expr] locals;
-	void resolve(Expr expr, uint depth){
-		locals[expr] = depth;
-	}
+
 
 	void visit(Stmt.Block stmt){
 		executeBlock(stmt.statements, new Environment(environment));
 	}
-	void visit(Stmt.Class stmt){
-		LoxValue superclass;
-		if(stmt.superclass !is null){
-			superclass = evaluate(stmt.superclass);
-			enforce(cast(LoxClass)superclass, new RuntimeError(stmt.superclass.name, "Superclass must be a class."));
-		}
-		environment.define(stmt.name.lexeme, new LoxNil());
-		if(stmt.superclass !is null){
-			environment = new Environment(environment);
-			environment.define("super", superclass);
-		}
-		LoxFunction[string] methods;
-		foreach(Stmt.Function method; stmt.methods){
-			LoxFunction func = new LoxFunction(method, environment, method.name.lexeme == "init");
-			methods[method.name.lexeme] = func;
-		}
-		LoxClass cls = new LoxClass(stmt.name.lexeme, cast(LoxClass)superclass, methods);
-		if(superclass !is null)
-			environment = environment.enclosing;
-		environment.assign(stmt.name, cls);
-	}
 	void visit(Stmt.Expression stmt){
 		evaluate(stmt.expression);
 	}
 	void visit(Stmt.Function stmt){
-		LoxFunction func = new LoxFunction(stmt, environment, false);
-		environment.define(stmt.name.lexeme, func);
+		LoxFunction func = new LoxFunction(stmt, environment);
+		environment.define(stmt.name.lexeme, TValue.cal(func));
 	}
 	void visit(Stmt.If stmt){
 		if(isTruthy(evaluate(stmt.condition)))
@@ -144,45 +116,41 @@ class Interpreter : Stmt.Visitor!void, Expr.Visitor!LoxValue {
 			execute(stmt.elseBranch);
 	}
 	void visit(Stmt.Print stmt){
-		version(LoxPrintMultiple){
-			writeln(stmt.expressions.map!(x => evaluate(x)).map!(x => x.toString).join('\t'));
-		} else {
-			LoxValue value = evaluate(stmt.expression);
-			writeln(value.toString);
-		}
+		TValue value = evaluate(stmt.expression);
+		writeln(tvalueToString(value));
 	}
 	void visit(Stmt.Return stmt){
-		LoxValue value = stmt.value !is null ? evaluate(stmt.value) : new LoxNil();
+		TValue value = stmt.value !is null ? evaluate(stmt.value) : TValue.nil(tvalueNil);
 		throw new Return(value);
 	}
 	void visit(Stmt.Var stmt){
-		environment.define(stmt.name.lexeme, stmt.initialiser is null ? new LoxNil() : evaluate(stmt.initialiser));
+		environment.define(stmt.name.lexeme, stmt.initialiser is null ? TValue.nil(tvalueNil) : evaluate(stmt.initialiser));
 	}
 	void visit(Stmt.While stmt){
 		while(isTruthy(evaluate(stmt.condition)))
 			execute(stmt.body);
 	}
 
-	LoxValue visit(Expr.Literal expr){
+	TValue visit(Expr.Literal expr){
 		return expr.value;
 	}
-	LoxValue visit(Expr.Grouping expr){
+	TValue visit(Expr.Grouping expr){
 		return evaluate(expr.expression);
 	}
-	LoxValue visit(Expr.Unary expr){
-		LoxValue right = evaluate(expr.right);
+	TValue visit(Expr.Unary expr){
+		TValue right = evaluate(expr.right);
 		switch(expr.operator.type){
 			case TokenType.MINUS:
 				checkNumberOperand(expr.operator, right);
-				return new LoxNum(-cast(LoxNum)right);
+				return TValue.dbl(-right.dblValue);
 			case TokenType.BANG:
-				return new LoxBool(!isTruthy(right));
+				return TValue.bln(!isTruthy(right));
 			default:
 				assert(0);
 		}
 	}
-	LoxValue visit(Expr.Logical expr){
-		LoxValue left = evaluate(expr.left);
+	TValue visit(Expr.Logical expr){
+		TValue left = evaluate(expr.left);
 		if(expr.operator.type == TokenType.OR){
 			if(isTruthy(left))
 				return left;
@@ -192,84 +160,59 @@ class Interpreter : Stmt.Visitor!void, Expr.Visitor!LoxValue {
 		}
 		return evaluate(expr.right);
 	}
-	LoxValue visit(Expr.Set expr){
-		LoxValue object = evaluate(expr.object);
-		if(!(cast(LoxInstance)object))
-			throw new RuntimeError(expr.name, "Only instances have fields.");
-		LoxValue value = evaluate(expr.value);
-		(cast(LoxInstance)object).set(expr.name, value);
-		return value;
-	}
-	LoxValue visit(Expr.Super expr){
-		uint distance = locals[expr];
-		LoxClass superclass = cast(LoxClass)environment.getAt(distance, "super");
-		LoxInstance object = cast(LoxInstance)environment.getAt(distance - 1, "this");
-		LoxFunction method = superclass.findMethod(expr.method.lexeme);
-		if(method is null)
-			throw new RuntimeError(expr.method, "Undefined property '" ~ expr.method.lexeme ~ "'.");
-		return method.bind(object);
-	}
-	LoxValue visit(Expr.This expr){
-		return lookUpVariable(expr.keyword, expr);
-	}
-	LoxValue visit(Expr.Binary expr){
-		LoxValue left = evaluate(expr.left);
-		LoxValue right = evaluate(expr.right); 
+	TValue visit(Expr.Binary expr){
+		TValue left = evaluate(expr.left);
+		TValue right = evaluate(expr.right); 
+		static string m(TokenType t, string op, string v, string vv){
+			return q{case %s:
+				checkNumberOperand(expr.operator, left);
+				checkNumberOperand(expr.operator, right);
+				return TValue.%s( left.%s %s right.%s );
+			}.format(t, v, vv, op, vv);
+		}
 		with(TokenType) switch(expr.operator.type){
-			static foreach(t, op; [ PLUS: "+", MINUS: "-", SLASH: "/", STAR: "*", GREATER: ">", GREATER_EQUAL: ">=", LESS: "<", LESS_EQUAL: "<=" ]){
-				case t:
-					static if(t == PLUS){
-						if(cast(LoxStr)left && cast(LoxStr)right)
-							return new LoxStr(cast(LoxStr)left ~ cast(LoxStr)right);
-						version(LoxConcatNonStrings){
-							if(cast(LoxStr)left || cast(LoxStr)right)
-								return new LoxStr(left.toString ~ right.toString);
-						}
-					}
-					checkNumberOperand(expr.operator, left);
-					checkNumberOperand(expr.operator, right);
-					return (cast(LoxNum)left).opBinary!op(cast(LoxNum)right);
-			}
+			static foreach(t, op; [ MINUS: "-", SLASH: "/", STAR: "*" ])
+				mixin(ctEval!(m(t, op, "dbl", "dblValue")));
+
+			case PLUS:
+				if(left.isDbl && right.isDbl)
+					return TValue.dbl(left.dblValue + right.dblValue);
+				else if(left.isStr && right.isStr)
+					return TValue.str(left.strValue ~ right.strValue);
+				version(LoxConcatNonStrings){
+					if(left.isStr || right.isStr)
+						return TValue.str(tvalueToString(left) ~ tvalueToString(right));
+				}
+				checkNumberOperand(expr.operator, left);
+				checkNumberOperand(expr.operator, right);
+
+			static foreach(t, op; [ GREATER: ">", GREATER_EQUAL: ">=", LESS: "<", LESS_EQUAL: "<=" ])
+				mixin(ctEval!(m(t, op, "bln", "dblValue")));
 
 			case BANG_EQUAL:
-			return new LoxBool(!isEqual(left, right));
+				return TValue.bln(!isEqual(left, right));
 			case EQUAL_EQUAL:
-			return new LoxBool(isEqual(left, right));
+				return TValue.bln(isEqual(left, right));
 			default:
-			assert(0);
+				assert(0);
 		}
 	}
-	LoxValue visit(Expr.Call expr){
-		LoxValue callee = evaluate(expr.callee);
-		if(!cast(LoxCallable)callee)
+	TValue visit(Expr.Call expr){
+		TValue callee = evaluate(expr.callee);
+		if(!callee.isCal)
 			throw new RuntimeError(expr.paren, "Can only call functions and classes.");
 		auto arguments = expr.arguments.map!(a => evaluate(a));
-		LoxCallable func = cast(LoxCallable)callee;
+		LoxCallable func = callee.calValue;
 		if(arguments.length != func.arity())
 			throw new RuntimeError(expr.paren, "Expected " ~ func.arity().to!string ~ " arguments but got " ~ arguments.length.to!string ~ ".");
 		return func.call(this, arguments.array);
 	}
-	LoxValue visit(Expr.Get expr){
-		LoxValue object = evaluate(expr.object);
-		if(auto ins = cast(LoxInstance)object)
-			return ins.get(expr.name);
-		throw new RuntimeError(expr.name, "Only instances have properties.");
+	TValue visit(Expr.Variable expr){
+		return environment.get(expr.name);
 	}
-	LoxValue visit(Expr.Variable expr){
-		return lookUpVariable(expr.name, expr);
-	}
-	private LoxValue lookUpVariable(Token name, Expr expr){
-		if(const distance = expr in locals)
-			return environment.getAt(*distance, name.lexeme);
-		else
-			return globals.get(name);
-	}
-	LoxValue visit(Expr.Assign expr){
-		LoxValue value = evaluate(expr.value);
-		if(const distance = expr in locals)
-			environment.assignAt(*distance, expr.name, value);
-		else
-			globals.assign(expr.name, value);
+	TValue visit(Expr.Assign expr){
+		TValue value = evaluate(expr.value);
+		environment.assign(expr.name, value);
 		return value;
 	}
 }
diff --git a/src/jlox/loxclass.d b/src/jlox/loxclass.d
deleted file mode 100644
index 44be38a..0000000
--- a/src/jlox/loxclass.d
+++ /dev/null
@@ -1,37 +0,0 @@
-module jlox.loxclass;
-
-import jlox.token;
-import jlox.interpreter;
-import jlox.loxinstance;
-import jlox.loxfunction;
-import common.util;
-
-class LoxClass : LoxCallable{
-	package const string name;
-	private const LoxClass superclass;
-	private const LoxFunction[string] methods;
-	mixin defaultCtor;
-
-	LoxFunction findMethod(string name) const{
-		if(auto method = name in methods)
-			return cast(LoxFunction)*method;
-		if(superclass !is null)
-			return superclass.findMethod(name);
-		return null;
-	}
-
-	int arity(){
-		if(auto initialiser = findMethod("init"))
-			return initialiser.arity();
-		return 0;
-	}
-	LoxValue call(Interpreter interpreter, LoxValue[] arguments){
-		LoxInstance instance = new LoxInstance(this);
-		LoxFunction initialiser = findMethod("init");
-		if(initialiser !is null)
-			initialiser.bind(instance).call(interpreter, arguments);
-		return instance;
-	}
-	override string toString() const => "class";
-}
-
diff --git a/src/jlox/loxfunction.d b/src/jlox/loxfunction.d
index 504369e..85bbb32 100644
--- a/src/jlox/loxfunction.d
+++ b/src/jlox/loxfunction.d
@@ -2,44 +2,31 @@ module jlox.loxfunction;
 
 import std.conv;
 
-import common.util;
 import jlox.token;
 import jlox.stmt;
 import jlox.interpreter;
 import jlox.environment;
-import jlox.loxinstance;
+import common.util;
 
 class LoxFunction : LoxCallable{
 	private Stmt.Function declaration;
 	private Environment closure;
-	private const bool isInitialiser;
 	mixin defaultCtor;
 	invariant{
 		assert(declaration && closure);
 	}
-
-	LoxFunction bind(LoxInstance instance){
-		Environment environment = new Environment(closure);
-		environment.define("this", instance);
-		return new LoxFunction(declaration, environment, isInitialiser);
-	}
 	
 	int arity() => declaration.params.length.to!int;
-	LoxValue call(Interpreter interpreter, LoxValue[] arguments){
+	TValue call(Interpreter interpreter, TValue[] arguments){
 		Environment environment = new Environment(closure);
 		foreach(i; 0 .. declaration.params.length)
 			environment.define(declaration.params[i].lexeme, arguments[i]);
 		try{
 			interpreter.executeBlock(declaration.body, environment);
 		} catch(Return returnValue){
-			if(isInitialiser)
-				return closure.getAt(0, "this");
-			return cast(LoxValue)returnValue.value;
+			return returnValue.value;
 		}
-		if(isInitialiser)
-			return closure.getAt(0, "this");
-		return new LoxNil();
+		return TValue.nil(tvalueNil);
 	}
-	override string toString() const => "function";
 }
 
diff --git a/src/jlox/loxinstance.d b/src/jlox/loxinstance.d
deleted file mode 100644
index f30d858..0000000
--- a/src/jlox/loxinstance.d
+++ /dev/null
@@ -1,27 +0,0 @@
-module jlox.loxinstance;
-
-import std.format : format;
-
-import jlox.token;
-import jlox.interpreter;
-import jlox.loxclass;
-import common.util;
-
-class LoxInstance : LoxValue{
-	private LoxClass cls;
-	private LoxValue[string] fields;
-	mixin defaultCtor;
-	override string toString() const => "<instance %s>".format(cls.name);
-
-	LoxValue get(Token name){
-		if(auto v = name.lexeme in fields)
-			return *v;
-		if(auto method = cls.findMethod(name.lexeme))
-			return method.bind(this);
-		throw new RuntimeError(name, "Undefined property '" ~ name.lexeme ~ "'.");
-	}
-	void set(Token name, LoxValue value){
-		fields[name.lexeme] = value;
-	}
-}
-
diff --git a/src/jlox/main.d b/src/jlox/main.d
index 17f176a..51e0e33 100644
--- a/src/jlox/main.d
+++ b/src/jlox/main.d
@@ -14,11 +14,6 @@ import jlox.parser;
 import jlox.interpreter;
 import jlox.expr;
 import jlox.stmt;
-import jlox.resolver;
-
-enum RetVal{
-	success = 0, other = 1, runtime = 2
-}
 
 private class MainException : Exception{
 	this(){
@@ -47,10 +42,7 @@ static class Lox{
 		hadError = true;
 	}
 	static void runtimeError(RuntimeError error){
-		if(error.token)
-			stderr.writeln(error.msg ~ "\n[line " ~ error.token.line.to!string ~ "]");
-		else
-			stderr.writeln(error.msg);
+		stderr.writeln(error.msg ~ "\n[line " ~ error.token.line.to!string ~ "]");
 		hadRuntimeError = true;
 	}
 
@@ -60,11 +52,7 @@ static class Lox{
 
 		Parser parser = new Parser(tokens);
 		Stmt[] statements = parser.parse();
-		if(hadError)
-			return;
 
-		Resolver resolver = new Resolver(interpreter);
-		resolver.resolve(statements);
 		if(hadError)
 			return;
 
@@ -89,8 +77,6 @@ static class Lox{
 	}
 }
 
-extern(C) int isatty(int);
-
 int main(string[] argv){
 	auto args = new Program("lox")
 		.add(new Argument("path").optional.acceptsFiles)
@@ -99,21 +85,17 @@ int main(string[] argv){
 	try{
 		if(args.arg("path") && args.option("command")){
 			stderr.writeln("Cant have both path and --cmd");
-			return RetVal.other;
+			return 3;
 		}
-		if(auto cmd = args.option("command")){
+		if(auto cmd = args.option("command"))
 			Lox.run(cmd);
-		} else if(auto path = args.arg("path")){
+		else if(auto path = args.arg("path"))
 			Lox.runFile(path);
-		} else {
-			if(isatty(stdin.fileno))
-				Lox.runPrompt();
-			else
-				Lox.runFile("/dev/stdin");
-		}
+		else
+			Lox.runPrompt();
 	} catch(MainException rte){
-		return Lox.hadError ? RetVal.other : RetVal.runtime;
+		return Lox.hadError ? 1 : 2;
 	}
-	return RetVal.success;
+	return 0;
 }
 
diff --git a/src/jlox/parser.d b/src/jlox/parser.d
index a314992..6ebc002 100644
--- a/src/jlox/parser.d
+++ b/src/jlox/parser.d
@@ -81,18 +81,9 @@ class Parser{
 	}
 
 	private Stmt printStatement(){
-		version(LoxPrintMultiple){
-			Expr[] values;
-			if(!check(TokenType.SEMICOLON)) do {
-				values ~= expression();
-			} while(match(TokenType.COMMA));
-			consume(TokenType.SEMICOLON, "Expect ';' after values.");
-			return new Stmt.Print(values);
-		} else {
-			Expr value = expression();
-			consume(TokenType.SEMICOLON, "Expect ';' after value.");
-			return new Stmt.Print(value);
-		}
+		Expr value = expression();
+		consume(TokenType.SEMICOLON, "Expect ';' after value.");
+		return new Stmt.Print(value);
 	}
 	private Stmt returnStatement(){
 		Token keyword = previous();
@@ -144,7 +135,7 @@ class Parser{
 		else
 			initialiser = expressionStatement();
 
-		Expr condition = check(TokenType.SEMICOLON) ? new Expr.Literal(new LoxBool(true)) : expression();
+		Expr condition = check(TokenType.SEMICOLON) ? new Expr.Literal(TValue.bln(true)) : expression();
 		consume(TokenType.SEMICOLON, "Expect ';' after loop condition.");
 
 		Expr increment;
@@ -197,11 +188,8 @@ class Parser{
 		if(match(TokenType.EQUAL)){
 			Token equals = previous();
 			Expr value = assignment();
-			if(auto v = cast(Expr.Variable)expr){
+			if(auto v = cast(Expr.Variable)expr)
 				return new Expr.Assign(v.name, value);
-			} else if(auto get = cast(Expr.Get)expr){
-				return new Expr.Set(get.object, get.name, value);
-			}
 			error(equals, "Invalid assignment target."); 
 		}
 		return expr;
@@ -283,14 +271,10 @@ class Parser{
 		}
 		Expr expr = primary();
 		while(true){ 
-			if(match(TokenType.LEFT_PAREN)){
+			if(match(TokenType.LEFT_PAREN))
 				expr = finishCall(expr);
-			} else if(match(TokenType.DOT)){
-				Token name = consume(TokenType.IDENTIFIER, "Expect property name after '.'.");
-				expr = new Expr.Get(expr, name);
-			} else {
+			else
 				break;
-			}
 		}
 		return expr;
 	}
@@ -298,26 +282,18 @@ class Parser{
 		if(match(TokenType.IDENTIFIER))
 			return new Expr.Variable(previous());
 		if(match(TokenType.FALSE))
-			return new Expr.Literal(new LoxBool(false));
+			return new Expr.Literal(TValue.bln(false));
 		if(match(TokenType.TRUE))
-			return new Expr.Literal(new LoxBool(true));
+			return new Expr.Literal(TValue.bln(true));
 		if(match(TokenType.NIL))
-			return new Expr.Literal(new LoxNil());
+			return new Expr.Literal(tvalueNil);
 		if(match(TokenType.NUMBER, TokenType.STRING))
 			return new Expr.Literal(previous().literal);
-		if(match(TokenType.THIS))
-			return new Expr.This(previous());
 		if(match(TokenType.LEFT_PAREN)){
 			Expr expr = expression();
 			consume(TokenType.RIGHT_PAREN, "Expect ')' after expression.");
 			return new Expr.Grouping(expr);
 		}
-		if(match(TokenType.SUPER)){
-			Token keyword = previous();
-			consume(TokenType.DOT, "Expect '.' after 'super'.");
-			Token method = consume(TokenType.IDENTIFIER, "Expect superclass method name.");
-			return new Expr.Super(keyword, method);
-		}
 		throw error(peek(), "Expect expression.");
 	}
 	private Stmt varDeclaration(){
@@ -328,28 +304,12 @@ class Parser{
 		consume(TokenType.SEMICOLON, "Expect ';' after variable declaration.");
 		return new Stmt.Var(name, initialiser);
 	}
-	private Stmt classDeclaration() {
-		Token name = consume(TokenType.IDENTIFIER, "Expect class name.");
-		Expr.Variable superclass;
-		if(match(TokenType.LESS)){
-			consume(TokenType.IDENTIFIER, "Expect superlcass name.");
-			superclass = new Expr.Variable(previous);
-		}
-		consume(TokenType.LEFT_BRACE, "Expect '{' before class body.");
-		Stmt.Function[] methods;
-		while(!check(TokenType.RIGHT_BRACE) && !isAtEnd)
-			methods ~= fun("method");
-		consume(TokenType.RIGHT_BRACE, "Expect '}' after class body.");
-		return new Stmt.Class(name, superclass, methods);
-	}
 	private Stmt declaration(){
 		try {
-			if(match(TokenType.VAR))
-				return varDeclaration();
 			if(match(TokenType.FUN))
 				return fun("function");
-			if(match(TokenType.CLASS))
-				return classDeclaration();
+			if(match(TokenType.VAR))
+				return varDeclaration();
 			return statement();
 		} catch(ParseError error){
 			synchronise();
diff --git a/src/jlox/resolver.d b/src/jlox/resolver.d
deleted file mode 100644
index c9dbf81..0000000
--- a/src/jlox/resolver.d
+++ /dev/null
@@ -1,198 +0,0 @@
-module jlox.resolver;
-
-import std.container.slist;
-import std.stdio;
-import std.algorithm;
-import std.range : enumerate;
-
-import jlox.main;
-import jlox.token;
-import jlox.stmt;
-import jlox.expr;
-import jlox.interpreter;
-import common.util;
-
-class Resolver : Stmt.Visitor!void, Expr.Visitor!void {
-	private enum FunctionType{ NONE, FUNCTION, INITIALISER, METHOD }
-	private enum ClassType{ NONE, CLASS, SUBCLASS }
-	private Interpreter interpreter;
-	this(Interpreter interpreter){
-		this.interpreter = interpreter;
-	}
-	private FunctionType currentFunction = FunctionType.NONE;
-	private ClassType currentClass = ClassType.NONE;
-	private SList!(bool[string]) scopes;
-	private void resolve(Stmt stmt) => stmt.accept(this);
-	private void resolve(Expr expr) => expr.accept(this);
-	void resolve(Stmt[] statements){
-		foreach(statement; statements)
-			resolve(statement);
-	}
-	private void resolveLocal(Expr expr, Token name){
-		foreach(i, scp; scopes[].enumerate){
-			if(name.lexeme in scp){
-				interpreter.resolve(expr, cast(uint)i);
-				return;
-			}
-		}
-	}
-	private void resolveFunction(Stmt.Function func, FunctionType type){
-		FunctionType enclosingFunction = currentFunction;
-		currentFunction = type;
-		scope(exit)
-			currentFunction = enclosingFunction;
-		beginScope();
-		foreach(param; func.params){
-			declare(param);
-			define(param);
-		}
-		resolve(func.body);
-		endScope();
-	}
-	private void endScope() => scopes.removeFront();
-	private void beginScope(){
-		bool[string] s;
-		scopes.insertFront(s);
-	}
-	private void declare(Token name){
-		if(scopes.empty)
-			return;
-		bool[string] scp = scopes.front;
-		if(name.lexeme in scp)
-			Lox.error(name, "Already a variable with this name in this scope.");
-		scp[name.lexeme] = false;
-	}
-	private void define(Token name){
-		if(scopes.empty)
-			return;
-		scopes.front[name.lexeme] = true;
-	}
-
-	void visit(Stmt.Block stmt){
-		beginScope();
-		resolve(stmt.statements);
-		endScope();
-	}
-	void visit(Stmt.Class stmt){
-		ClassType enclosingClass = currentClass;
-		currentClass = ClassType.CLASS;
-		scope(exit)
-			currentClass = enclosingClass;
-		declare(stmt.name);
-		define(stmt.name);
-		if(stmt.superclass !is null){
-			currentClass = ClassType.SUBCLASS;
-			if(stmt.name.lexeme == stmt.superclass.name.lexeme)
-				Lox.error(stmt.superclass.name, "A class can't inherit from itself.");
-			resolve(stmt.superclass);
-		}
-		if(stmt.superclass !is null){
-			beginScope();
-			scopes.front["super"] = true;
-		}
-		beginScope();
-		scopes.front["this"] = true;
-		foreach(method; stmt.methods){
-			FunctionType declaration = FunctionType.METHOD;
-			if(method.name.lexeme == "init")
-				declaration = FunctionType.INITIALISER;
-			resolveFunction(method, declaration); 
-		}
-		endScope();
-		if(stmt.superclass !is null)
-			endScope();
-	}
-	void visit(Stmt.Var stmt){
-		declare(stmt.name);
-		if(stmt.initialiser !is null)
-			resolve(stmt.initialiser);
-		define(stmt.name);
-	}
-	void visit(Stmt.Function stmt){
-		declare(stmt.name);
-		define(stmt.name);
-		resolveFunction(stmt, FunctionType.FUNCTION);
-	}
-	void visit(Expr.Variable expr){
-		if(!scopes.empty && scopes.front.get(expr.name.lexeme, true) == false)
-			Lox.error(expr.name, "Can't read local variable in its own initializer.");
-		resolveLocal(expr, expr.name);
-	}
-	void visit(Expr.Assign expr){
-		resolve(expr.value);
-		resolveLocal(expr, expr.name);
-	}
-
-	void visit(Stmt.Expression stmt){
-		resolve(stmt.expression);
-	}
-	void visit(Stmt.If stmt){
-		resolve(stmt.condition);
-		resolve(stmt.thenBranch);
-		if(stmt.elseBranch !is null)
-			resolve(stmt.elseBranch);
-	}
-	void visit(Stmt.Print stmt){
-		version(LoxPrintMultiple){
-			foreach(expr; stmt.expressions)
-				resolve(expr);
-		} else {
-			resolve(stmt.expression);
-		}
-	}
-	void visit(Stmt.Return stmt){
-		if(currentFunction == FunctionType.NONE)
-			Lox.error(stmt.keyword, "Can't return from top-level code.");
-		if(stmt.value !is null){
-			if(currentFunction == FunctionType.INITIALISER)
-				Lox.error(stmt.keyword, "Can't return a value from an initializer.");
-			resolve(stmt.value);
-		}
-	}
-	void visit(Stmt.While stmt){
-		resolve(stmt.condition);
-		resolve(stmt.body);
-	}
-	void visit(Expr.Binary expr){
-		resolve(expr.left);
-		resolve(expr.right);
-	}
-	void visit(Expr.Call expr){
-		resolve(expr.callee);
-		foreach(argument; expr.arguments)
-			resolve(argument);
-	}
-	void visit(Expr.Get expr){
-		resolve(expr.object);
-	}
-	void visit(Expr.Grouping expr){
-		resolve(expr.expression);
-	}
-	void visit(Expr.Literal expr){}
-	void visit(Expr.Logical expr){
-		resolve(expr.left);
-		resolve(expr.right);
-	}
-	void visit(Expr.Set expr){
-		resolve(expr.value);
-		resolve(expr.object);
-	}
-	void visit(Expr.Super expr){
-		if(currentClass == ClassType.NONE)
-			Lox.error(expr.keyword, "Can't use 'super' outside of a class.");
-		else if (currentClass != ClassType.SUBCLASS)
-			Lox.error(expr.keyword, "Can't use 'super' in a class with no superclass.");
-		resolveLocal(expr, expr.keyword);
-	}
-	void visit(Expr.This expr){
-		if(currentClass == ClassType.NONE){
-			Lox.error(expr.keyword, "Can't use 'this' outside of a class.");
-			return;
-		}
-		resolveLocal(expr, expr.keyword);
-	}
-	void visit(Expr.Unary expr){
-		resolve(expr.right);
-	}
-}
-
diff --git a/src/jlox/scanner.d b/src/jlox/scanner.d
index 8da932f..5d0a412 100644
--- a/src/jlox/scanner.d
+++ b/src/jlox/scanner.d
@@ -6,9 +6,11 @@ import std.conv;
 import jlox.token;
 import jlox.tokentype;
 import jlox.main;
-import common.util;
 
-class Scanner{
+private bool isAlpha_(dchar c)    => c.isAlpha    || c == '_';
+private bool isAlphaNum_(dchar c) => c.isAlphaNum || c == '_';
+
+class Scanner {
 	private string source;
 	private Token[] tokens;
 	private uint start = 0;
@@ -28,7 +30,7 @@ class Scanner{
 		current++;
 		return true;
 	}
-	private void addToken(TokenType type, LoxValue literal = new LoxNil()){
+	private void addToken(TokenType type, TValue literal = TValue.nil(tvalueNil)){
 		string text = source[start .. current];
 		tokens ~= new Token(type, text, literal, line);
 	}
@@ -52,7 +54,7 @@ class Scanner{
 		}
 		advance();
 		string value = source[start + 1 .. current -1];
-		addToken(TokenType.STRING, new LoxStr(value));
+		addToken(TokenType.STRING, TValue.str(value));
 	}
 	private void number(){
 		while(peek().isDigit)
@@ -62,7 +64,7 @@ class Scanner{
 			while(peek().isDigit)
 				advance();
 		}
-		addToken(TokenType.NUMBER, new LoxNum(source[start .. current].to!double));
+		addToken(TokenType.NUMBER, TValue.dbl(source[start .. current].to!double));
 	}
 	private TokenType keywords(string word){
 		with(TokenType) switch(word){
diff --git a/src/jlox/stmt.d b/src/jlox/stmt.d
index 64d35ae..ad701c8 100644
--- a/src/jlox/stmt.d
+++ b/src/jlox/stmt.d
@@ -12,7 +12,6 @@ import jlox.expr;
 abstract class Stmt{
 	interface Visitor(R){
 		R visit(Block expr);
-		R visit(Class expr);
 		R visit(Expression expr);
 		R visit(Function expr);
 		R visit(If expr);
@@ -34,12 +33,6 @@ abstract class Stmt{
 		Stmt[] statements;
 		mixin defCtorAndAccept;
 	}
-	static class Class : typeof(this){
-		Token name;
-		Expr.Variable superclass;
-		Function[] methods;
-		mixin defCtorAndAccept;
-	}
 	static class Expression : typeof(this){
 		Expr expression;
 		mixin defCtorAndAccept;
@@ -57,10 +50,7 @@ abstract class Stmt{
 		mixin defCtorAndAccept;
 	}
 	static class Print : typeof(this){
-		version(LoxPrintMultiple)
-			Expr[] expressions;
-		else
-			Expr expression;
+		Expr expression;
 		mixin defCtorAndAccept;
 	}
 	static class Return : typeof(this){
diff --git a/src/jlox/token.d b/src/jlox/token.d
index dcbf5a3..fb2c117 100644
--- a/src/jlox/token.d
+++ b/src/jlox/token.d
@@ -1,70 +1,48 @@
 module jlox.token;
 
-import std.stdio;
 import std.conv;
-import std.format : format;
 
-import common.util;
+import taggedalgebraic;
+
 import jlox.tokentype;
 import jlox.interpreter;
-import jlox.loxclass;
-import jlox.loxinstance;
-import jlox.loxfunction;
 
-abstract interface LoxValue{
-	string toString() const;
-	final bool equals(LoxValue v){
-		if(this.classinfo != v.classinfo)
-			return false;
-		else if(auto s = cast(LoxStr)this)
-			return s.str == (cast(LoxStr)v).str;
-		else if(auto n = cast(LoxNum)this)
-			return n.num == (cast(LoxNum)v).num;
-		else if(auto b = cast(LoxBool)this)
-			return b.bln == (cast(LoxBool)v).bln;
-		return this == v;
-	};
-}
-interface LoxCallable : LoxValue{
+interface LoxCallable{
 	int arity();
-	LoxValue call(Interpreter interpreter, LoxValue[] arguments);
+	TValue call(Interpreter interpreter, TValue[] arguments);
 }
-class LoxStr : LoxValue{
-	immutable string str;
-	alias str this;
-	mixin defaultCtor;
-	override string toString() const => str;
+private struct Value{
+	string str;
+	double dbl;
+	bool bln;
+	LoxCallable cal;
+	struct Nil{}
+	Nil nil;
 }
-class LoxBool : LoxValue{
-	immutable bool bln;
-	alias bln this;
-	mixin defaultCtor;
-	override string toString() const => bln.to!string;
-}
-class LoxNum : LoxValue{
-	immutable double num;
-	alias num this;
-	mixin defaultCtor;
-	override string toString() const => num.to!string;
-	auto opBinary(string op)(const LoxNum rhs) const{
-		mixin("auto v = num", op, "rhs.num;");
-		static if(is(typeof(v) == bool))
-			return new LoxBool(v);
-		else
-			return new LoxNum(v);
+alias TValue = TaggedUnion!Value;
+immutable tvalueNil = Value.Nil();
+string tvalueToString(TValue val){
+	final switch(val.kind){
+		case TValue.Kind.str:
+			return val.strValue;
+		case TValue.Kind.dbl:
+			return val.dblValue.to!string;
+		case TValue.Kind.bln:
+			return val.blnValue ? "true" : "false";
+		case TValue.Kind.cal:
+			return "<function>";
+		case TValue.Kind.nil:
+			return "nil";
 	}
 }
-class LoxNil : LoxValue{
-	override string toString() const => "<nil>";
-}
 
 class Token{
 	TokenType type;
 	string lexeme;
-	LoxValue literal;
+	TValue literal;
 	int line; 
 
-	this(TokenType type, string lexeme, LoxValue literal, int line) {
+	this(TokenType type, string lexeme, TValue literal, int line) {
 		this.type = type;
 		this.lexeme = lexeme;
 		this.literal = literal;
diff --git a/test/all.d b/test/all.d
index a7c3542..5b79f0e 100755
--- a/test/all.d
+++ b/test/all.d
@@ -1,56 +1,22 @@
 #!/bin/env rdmd
 
-import std.stdio;
 import std.process;
-import std.concurrency;
 import std.conv;
-import std.string, std.format;
-import std.algorithm, std.range;
 
 void main(){
-	"./test/ops.lox".match("1\n2\n3\n4\n5\n6\n7\ntrue\nfalse\ntrue\ntrue\nhello, world\n");
-	"./test/shortcircuit.lox".match("true\nAAAA!\nAAAA!\nAAAA?\n");
-	"./test/closure.lox".match("1\n2\n");
-	"./test/scope.lox".match("global first first second first ".replace(' ', '\n').repeat(2).join("\n"));
-	"./test/fib_for.lox".match(fib(6765));
-	"./test/fib_recursive.lox".match(fib(34));
-	"./test/fib_closure.lox".match(fib(34));
-	"./test/class.lox".match("The German chocolate cake is delicious!\n");
-	"./test/super.lox".match("Fry until golden brown.\nPipe full of custard and coat with chocolate.\nA method\n");
-
-	"./test/err/invalid_syntax.lox".shouldFail(RetVal.other);
-	"./test/err/already_defined.lox".shouldFail(RetVal.other, "Already a variable with this name");
-	"./test/err/undefined_var.lox".shouldFail(RetVal.runtime, "Undefined variable");
-	"./test/err/self_ref_vardecl.lox".shouldFail(RetVal.runtime, "Undefined variable");
-	"./test/err/global_scope_return.lox".shouldFail(RetVal.other, "Can't return from top-level code");
-	"./test/err/super_outside_class.lox".shouldFail(RetVal.other, "Can't use 'super' outside of a class");
-	"./test/err/super_without_superclass.lox".shouldFail(RetVal.other, "Can't use 'super' in a class with no superclass");
-}
-
-enum RetVal{
-	success = 0, other = 1, runtime = 2
-}
-
-string fib(uint n){
-	string r = "";
-	double a = 0;
-	double temp;
-	for(double b = 1; a <= n; b = temp + b){
-		r ~= a.to!string ~ "\n";
-		temp = a;
-		a = b;
+	string fib(uint n){
+		string r = "";
+		double a = 0;
+		double temp;
+		for(double b = 1; a <= n; b = temp + b){
+			r ~= a.to!string ~ "\n";
+			temp = a;
+			a = b;
+		}
+		return r;
 	}
-	return r;
-}
-auto run(string file) => [ "./lox", file ].execute;
-void match(string file, string correct){
-	auto res = file.run.output;
-	assert(res == correct, "Match %s failed\n-- Got --\n%s\n-- Expected --\n%s".format(file, res, correct));
-}
-void shouldFail(string file, int code = 1, string msg = null){
-	auto c = file.run;
-	assert(c.status == code, "Expected %s to fail with code %d but got %d".format(file, code, c.status));
-	assert(!msg || c.output.toLower.indexOf(msg.toLower) >= 0, "ShouldFail %s failed\n-- Got --\n%s\n-- Expected --\n%s".format(file, c.output, msg));
-	assert(c.output.indexOf("_Dmain") == -1, "ShouldFail %s got D exception\n%s".format(file, c.output));
+	assert([ "./lox", "test/fib21.lox" ].execute.output == fib(6765));
+	assert([ "./lox", "test/fib10.lox" ].execute.output == fib(34));
+	assert([ "./lox", "test/closure.lox" ].execute.output == "1\n2\n");
 }
 
diff --git a/test/class.lox b/test/class.lox
deleted file mode 100644
index 87bfb6a..0000000
--- a/test/class.lox
+++ /dev/null
@@ -1,21 +0,0 @@
-
-class Cake{
-	init(goodness){
-		this.adjective = this.rate(goodness);
-	}
-	rate(goodness){
-		if(goodness)
-			return "delicious";
-		else
-			return "horrendous";
-	}
-	taste(){
-		print "The " + this.flavor + " cake is " + this.adjective + "!";
-	}
-}
-
-var cake = Cake(true);
-cake.flavor = "German chocolate";
-var t = cake.taste;
-t();
-
diff --git a/test/err/already_defined.lox b/test/err/already_defined.lox
deleted file mode 100644
index 6d142d4..0000000
--- a/test/err/already_defined.lox
+++ /dev/null
@@ -1,6 +0,0 @@
-
-fun bad(){
-	var a = "first";
-	var a = "second";
-}
-
diff --git a/test/err/global_scope_return.lox b/test/err/global_scope_return.lox
deleted file mode 100644
index c0658c2..0000000
--- a/test/err/global_scope_return.lox
+++ /dev/null
@@ -1,3 +0,0 @@
-
-return ":)";
-
diff --git a/test/err/invalid_syntax.lox b/test/err/invalid_syntax.lox
deleted file mode 100644
index 24823b1..0000000
--- a/test/err/invalid_syntax.lox
+++ /dev/null
@@ -1,3 +0,0 @@
-
-foo
-
diff --git a/test/err/self_ref_vardecl.lox b/test/err/self_ref_vardecl.lox
deleted file mode 100644
index e58a127..0000000
--- a/test/err/self_ref_vardecl.lox
+++ /dev/null
@@ -1,3 +0,0 @@
-
-var x = x + 1;
-
diff --git a/test/err/super_outside_class.lox b/test/err/super_outside_class.lox
deleted file mode 100644
index 4a14239..0000000
--- a/test/err/super_outside_class.lox
+++ /dev/null
@@ -1,3 +0,0 @@
-
-super.notEvenInAClass();
-
diff --git a/test/err/super_without_superclass.lox b/test/err/super_without_superclass.lox
deleted file mode 100644
index d6b4cdc..0000000
--- a/test/err/super_without_superclass.lox
+++ /dev/null
@@ -1,8 +0,0 @@
-
-class Eclair{
-	cook(){
-		super.cook();
-		print "Pipe full of crème pâtissière.";
-	}
-}
-
diff --git a/test/err/undefined_var.lox b/test/err/undefined_var.lox
deleted file mode 100644
index b3162ca..0000000
--- a/test/err/undefined_var.lox
+++ /dev/null
@@ -1,3 +0,0 @@
-
-print hello;
-
diff --git a/test/fib_recursive.lox b/test/fib10.lox
similarity index 100%
rename from test/fib_recursive.lox
rename to test/fib10.lox
diff --git a/test/fib_for.lox b/test/fib21.lox
similarity index 100%
rename from test/fib_for.lox
rename to test/fib21.lox
diff --git a/test/fib_closure.lox b/test/fib_closure.lox
deleted file mode 100644
index 42c8fe8..0000000
--- a/test/fib_closure.lox
+++ /dev/null
@@ -1,18 +0,0 @@
-
-fun fibonacci(){
-	var a = 0;
-	var b = 1;
-	fun f(){
-		var next = a;
-		a = b;
-		b = next + b;
-		return next;
-	}
-	return f;
-}
-
-var nextFibonacci = fibonacci();
-
-for(var i = 0; i < 10; i = i + 1)
-	print nextFibonacci();
-
diff --git a/test/ops.lox b/test/ops.lox
deleted file mode 100644
index 30da068..0000000
--- a/test/ops.lox
+++ /dev/null
@@ -1,17 +0,0 @@
-
-print 2 - 1;
-print 1 + 1;
-print 6 / 2;
-print 2 * 2;
-print 2 * 3 - 1;
-print 1 + 2 + 3;
-print 1 + 2 * 3;
-
-print 2 <= 3 or false;
-print 1 > 2;
-
-print 1 == 1;
-print 1 != 2;
-
-print "hello, " + "world";
-
diff --git a/test/scope.lox b/test/scope.lox
deleted file mode 100644
index 4b9eadc..0000000
--- a/test/scope.lox
+++ /dev/null
@@ -1,19 +0,0 @@
-
-var a = "global";
-
-fun f(){
-	print a;
-	var a = "first";
-	print a;
-	{
-		print a;
-		var a = "second";
-		print a;
-	}
-	print a;
-}
-
-f();
-print "";
-f();
-
diff --git a/test/shortcircuit.lox b/test/shortcircuit.lox
deleted file mode 100644
index 7e03749..0000000
--- a/test/shortcircuit.lox
+++ /dev/null
@@ -1,12 +0,0 @@
-
-fun scream(extra){
-	extra = extra or "!";
-	print "AAAA" + extra;
-}
-
-print nil or true;
-
-scream(false);
-scream(nil);
-scream("?");
-
diff --git a/test/super.lox b/test/super.lox
deleted file mode 100644
index dec5f8d..0000000
--- a/test/super.lox
+++ /dev/null
@@ -1,36 +0,0 @@
-
-class Doughnut{
-	cook(){
-		print "Fry until golden brown.";
-	}
-}
-
-class BostonCream < Doughnut{
-	cook(){
-		super.cook();
-		print "Pipe full of custard and coat with chocolate.";
-	}
-}
-
-BostonCream().cook();
-
-
-class A{
-	method(){
-		print "A method";
-	}
-}
-
-class B < A{
-	method(){
-		print "B method";
-	}
-	test(){
-		super.method();
-	}
-}
-
-class C < B{}
-
-C().test();
-