diff --git a/cmd/bench/main.go b/cmd/bench/main.go
index 17a8093..730ce6b 100644
--- a/cmd/bench/main.go
+++ b/cmd/bench/main.go
@@ -193,7 +193,7 @@ func compileFile(file *ast.File) (time.Duration, *compiler.Bytecode, error) {
 
 	start := time.Now()
 
-	c := compiler.NewCompiler(symTable, nil, nil)
+	c := compiler.NewCompiler(symTable, nil, nil, nil)
 	if err := c.Compile(file); err != nil {
 		return time.Since(start), nil, err
 	}
diff --git a/cmd/tengo/main.go b/cmd/tengo/main.go
index f9d19b5..81e3faf 100644
--- a/cmd/tengo/main.go
+++ b/cmd/tengo/main.go
@@ -186,6 +186,8 @@ func runREPL(in io.Reader, out io.Writer) {
 		symbolTable.DefineBuiltin(idx, fn.Name)
 	}
 
+	var constants []objects.Object
+
 	for {
 		_, _ = fmt.Fprintf(out, replPrompt)
 
@@ -204,13 +206,15 @@ func runREPL(in io.Reader, out io.Writer) {
 
 		file = addPrints(file)
 
-		c := compiler.NewCompiler(symbolTable, nil, nil)
+		c := compiler.NewCompiler(symbolTable, constants, nil, nil)
 		if err := c.Compile(file); err != nil {
 			_, _ = fmt.Fprintf(out, "Compilation error:\n %s\n", err.Error())
 			continue
 		}
 
-		machine := runtime.NewVM(c.Bytecode(), globals)
+		bytecode := c.Bytecode()
+
+		machine := runtime.NewVM(bytecode, globals)
 		if err != nil {
 			_, _ = fmt.Fprintf(out, "VM error:\n %s\n", err.Error())
 			continue
@@ -219,6 +223,8 @@ func runREPL(in io.Reader, out io.Writer) {
 			_, _ = fmt.Fprintf(out, "Execution error:\n %s\n", err.Error())
 			continue
 		}
+
+		constants = bytecode.Constants
 	}
 }
 
@@ -231,7 +237,7 @@ func compileSrc(src []byte, filename string) (*compiler.Bytecode, error) {
 		return nil, err
 	}
 
-	c := compiler.NewCompiler(nil, nil, nil)
+	c := compiler.NewCompiler(nil, nil, nil, nil)
 	if err := c.Compile(file); err != nil {
 		return nil, err
 	}
diff --git a/compiler/compiler.go b/compiler/compiler.go
index 17a6d3a..13967e7 100644
--- a/compiler/compiler.go
+++ b/compiler/compiler.go
@@ -34,7 +34,7 @@ type Compiler struct {
 // a new symbol table and use the default builtin functions. Likewise, standard
 // modules can be explicitly provided if user wants to add or remove some modules.
 // By default, Compile will use all the standard modules otherwise.
-func NewCompiler(symbolTable *SymbolTable, stdModules map[string]*objects.ImmutableMap, trace io.Writer) *Compiler {
+func NewCompiler(symbolTable *SymbolTable, constants []objects.Object, stdModules map[string]*objects.ImmutableMap, trace io.Writer) *Compiler {
 	mainScope := CompilationScope{
 		instructions: make([]byte, 0),
 	}
@@ -55,6 +55,7 @@ func NewCompiler(symbolTable *SymbolTable, stdModules map[string]*objects.Immuta
 
 	return &Compiler{
 		symbolTable:     symbolTable,
+		constants:       constants,
 		scopes:          []CompilationScope{mainScope},
 		scopeIndex:      0,
 		loopIndex:       -1,
@@ -591,7 +592,7 @@ func (c *Compiler) SetModuleLoader(moduleLoader ModuleLoader) {
 }
 
 func (c *Compiler) fork(moduleName string, symbolTable *SymbolTable) *Compiler {
-	child := NewCompiler(symbolTable, c.stdModules, c.trace)
+	child := NewCompiler(symbolTable, nil, c.stdModules, c.trace)
 	child.moduleName = moduleName       // name of the module to compile
 	child.parent = c                    // parent to set to current compiler
 	child.moduleLoader = c.moduleLoader // share module loader
diff --git a/compiler/compiler_test.go b/compiler/compiler_test.go
index 6e16db9..a139143 100644
--- a/compiler/compiler_test.go
+++ b/compiler/compiler_test.go
@@ -976,7 +976,7 @@ func traceCompile(input string, symbols map[string]objects.Object) (res *compile
 	}
 
 	tr := &tracer{}
-	c := compiler.NewCompiler(symTable, nil, tr)
+	c := compiler.NewCompiler(symTable, nil, nil, tr)
 	parsed, err := p.ParseFile()
 	if err != nil {
 		return
diff --git a/runtime/vm_test.go b/runtime/vm_test.go
index 103e785..b963330 100644
--- a/runtime/vm_test.go
+++ b/runtime/vm_test.go
@@ -230,7 +230,7 @@ func traceCompileRun(file *ast.File, symbols map[string]objects.Object, userModu
 	}
 
 	tr := &tracer{}
-	c := compiler.NewCompiler(symTable, nil, tr)
+	c := compiler.NewCompiler(symTable, nil, nil, tr)
 	c.SetModuleLoader(func(moduleName string) ([]byte, error) {
 		if src, ok := userModules[moduleName]; ok {
 			return []byte(src), nil
diff --git a/script/script.go b/script/script.go
index 4b9ade9..6a56f45 100644
--- a/script/script.go
+++ b/script/script.go
@@ -94,7 +94,7 @@ func (s *Script) Compile() (*Compiled, error) {
 		return nil, fmt.Errorf("parse error: %s", err.Error())
 	}
 
-	c := compiler.NewCompiler(symbolTable, stdModules, nil)
+	c := compiler.NewCompiler(symbolTable, nil, stdModules, nil)
 
 	if s.userModuleLoader != nil {
 		c.SetModuleLoader(s.userModuleLoader)