Fix VM memory allocation optimizations by reducing what we allocate on the heap

internal/object/function.go

@@ -12,15 +12,15 @@ type Function struct {
 	Env        *Environment
 }
 
-func (f *Function) Bool() bool {
+func (f Function) Bool() bool {
 	return false
 }
 
-func (f *Function) Type() Type {
+func (f Function) Type() Type {
 	return FunctionType
 }
 
-func (f *Function) Inspect() string {
+func (f Function) Inspect() string {
 	var out bytes.Buffer
 
 	params := []string{}
@@ -38,7 +38,7 @@ func (f *Function) Inspect() string {
 	return out.String()
 }
 
-func (f *Function) String() string {
+func (f Function) String() string {
 	return f.Inspect()
 }
 
@@ -46,18 +46,18 @@ type ReturnValue struct {
 	Value Object
 }
 
-func (rv *ReturnValue) Bool() bool {
+func (rv ReturnValue) Bool() bool {
 	return true
 }
 
-func (rv *ReturnValue) Type() Type {
+func (rv ReturnValue) Type() Type {
 	return ReturnType
 }
 
-func (rv *ReturnValue) Inspect() string {
+func (rv ReturnValue) Inspect() string {
 	return rv.Value.Inspect()
 }
 
-func (rv *ReturnValue) String() string {
+func (rv ReturnValue) String() string {
 	return rv.Inspect()
 }