line counting in bytecode

compiler/bytecode.go

@@ -232,3 +232,18 @@ func GetOperandCount(op Opcode) int {
 func InstructionSize(op Opcode) int {
 	return 1 + (GetOperandCount(op) * 2) // 1 byte opcode + 2 bytes per operand
 }
+
+var opcodeNames = map[Opcode]string{
+	OpLoadConst:   "OP_LOAD_CONST",
+	OpLoadLocal:   "OP_LOAD_LOCAL",
+	OpStoreLocal:  "OP_STORE_LOCAL",
+	OpAdd:         "OP_ADD",
+	OpSub:         "OP_SUB",
+	OpMul:         "OP_MUL",
+	OpDiv:         "OP_DIV",
+	OpJump:        "OP_JUMP",
+	OpJumpIfTrue:  "OP_JUMP_TRUE",
+	OpJumpIfFalse: "OP_JUMP_FALSE",
+	OpReturn:      "OP_RETURN",
+	OpEcho:        "OP_ECHO",
+}

compiler/compiler.go

@@ -38,6 +38,11 @@ func (c *Compiler) Compile(program *parser.Program) (*Chunk, []CompileError) {
 
 // Statement compilation
 func (c *Compiler) compileStatement(stmt parser.Statement) {
+	// Extract line from any statement that has position info
+	if lineNode := c.getLineFromNode(stmt); lineNode != 0 {
+		c.current.SetLine(lineNode)
+	}
+
 	switch s := stmt.(type) {
 	case *parser.StructStatement:
 		c.compileStructStatement(s)
@@ -72,6 +77,10 @@ func (c *Compiler) compileStatement(stmt parser.Statement) {
 
 // Expression compilation
 func (c *Compiler) compileExpression(expr parser.Expression) {
+	if lineNode := c.getLineFromNode(expr); lineNode != 0 {
+		c.current.SetLine(lineNode)
+	}
+
 	switch e := expr.(type) {
 	case *parser.Identifier:
 		c.compileIdentifier(e)
@@ -836,14 +845,94 @@ func (c *Compiler) findStructFieldIndex(structID uint16, fieldName string) int {
 	return -1
 }
 
+// Enhanced error reporting
 func (c *Compiler) addError(message string) {
 	c.errors = append(c.errors, CompileError{
 		Message: message,
-		Line:    0, // TODO: Add line tracking
-		Column:  0, // TODO: Add column tracking
+		Line:    c.current.CurrentLine,
+		Column:  0, // Column tracking would need more work
 	})
 }
 
 // Error reporting
 func (c *Compiler) Errors() []CompileError { return c.errors }
 func (c *Compiler) HasErrors() bool        { return len(c.errors) > 0 }
+
+// Helper to extract line info from AST nodes
+func (c *Compiler) getLineFromNode(node any) int {
+	// Since AST nodes don't store position, we'd need to modify the parser
+	// For now, track during compilation by passing line info through
+	return 0 // Placeholder
+}
+
+// Bytecode disassembler helper for debugging
+func DisassembleInstruction(chunk *Chunk, offset int) int {
+	if offset >= len(chunk.Code) {
+		return offset
+	}
+
+	line := 0
+	if offset < len(chunk.Lines) {
+		line = chunk.Lines[offset]
+	}
+
+	fmt.Printf("%04d ", offset)
+	if offset > 0 && line == chunk.Lines[offset-1] {
+		fmt.Print("   | ")
+	} else {
+		fmt.Printf("%4d ", line)
+	}
+
+	op := Opcode(chunk.Code[offset])
+	fmt.Printf("%-16s", opcodeNames[op])
+
+	switch op {
+	case OpLoadConst, OpLoadLocal, OpStoreLocal:
+		operand := uint16(chunk.Code[offset+1]) | (uint16(chunk.Code[offset+2]) << 8)
+		fmt.Printf(" %4d", operand)
+		if op == OpLoadConst && int(operand) < len(chunk.Constants) {
+			fmt.Printf(" '")
+			printValue(chunk.Constants[operand])
+			fmt.Printf("'")
+		}
+		return offset + 3
+	case OpJump, OpJumpIfTrue, OpJumpIfFalse:
+		jump := uint16(chunk.Code[offset+1]) | (uint16(chunk.Code[offset+2]) << 8)
+		fmt.Printf(" %4d -> %d", jump, offset+3+int(jump))
+		return offset + 3
+	default:
+		return offset + 1
+	}
+}
+
+func printValue(value Value) {
+	switch value.Type {
+	case ValueNil:
+		fmt.Print("nil")
+	case ValueBool:
+		fmt.Print(value.Data.(bool))
+	case ValueNumber:
+		fmt.Printf("%.2f", value.Data.(float64))
+	case ValueString:
+		fmt.Print(value.Data.(string))
+	default:
+		fmt.Printf("<%s>", valueTypeString(value.Type))
+	}
+}
+
+func valueTypeString(vt ValueType) string {
+	switch vt {
+	case ValueTable:
+		return "table"
+	case ValueFunction:
+		return "function"
+	case ValueStruct:
+		return "struct"
+	case ValueArray:
+		return "array"
+	case ValueUpvalue:
+		return "upvalue"
+	default:
+		return "unknown"
+	}
+}

compiler/state.go

@@ -24,6 +24,7 @@ type CompilerState struct {
 	LoopStart     int            // Start of current loop for continue
 	LoopDepth     int            // Current loop nesting depth
 	parent        *CompilerState // Parent compiler state for nested functions
+	CurrentLine   int            // Current source line being compiled
 }
 
 // Local represents a local variable during compilation
@@ -216,7 +217,7 @@ func (cs *CompilerState) valueKey(value Value) string {
 // Bytecode emission methods
 func (cs *CompilerState) EmitByte(byte uint8) {
 	cs.Chunk.Code = append(cs.Chunk.Code, byte)
-	cs.Chunk.Lines = append(cs.Chunk.Lines, 0) // Line will be set by caller
+	cs.Chunk.Lines = append(cs.Chunk.Lines, cs.CurrentLine)
 }
 
 func (cs *CompilerState) EmitBytes(bytes ...uint8) {
@@ -290,3 +291,7 @@ func (cs *CompilerState) EmitContinue() {
 		cs.ContinueJumps = append(cs.ContinueJumps, jumpOffset)
 	}
 }
+
+func (cs *CompilerState) SetLine(line int) {
+	cs.CurrentLine = line
+}