restructure project

internal/object/null.go

@@ -0,0 +1,26 @@
+package object
+
+type Null struct{}
+
+func (n *Null) Bool() bool {
+	return false
+}
+
+func (n *Null) Type() ObjectType {
+	return NULL_OBJ
+}
+
+func (n *Null) Inspect() string {
+	return "null"
+}
+
+func (n *Null) String() string {
+	return n.Inspect()
+}
+
+func (n *Null) Compare(other Object) int {
+	if _, ok := other.(*Null); ok {
+		return 0
+	}
+	return 1
+}