diff --git a/config/lang/ast/ast.go b/config/lang/ast/ast.go
index 3bb748ccc..c9ae1b882 100644
--- a/config/lang/ast/ast.go
+++ b/config/lang/ast/ast.go
@@ -3,6 +3,8 @@ package ast
 // Node is the interface that all AST nodes must implement.
 type Node interface{}
 
+//go:generate stringer -type=Type
+
 // Type is the type of a literal.
 type Type uint
 
diff --git a/config/lang/ast/type_string.go b/config/lang/ast/type_string.go
new file mode 100644
index 000000000..59c336f5a
--- /dev/null
+++ b/config/lang/ast/type_string.go
@@ -0,0 +1,17 @@
+// generated by stringer -type=Type; DO NOT EDIT
+
+package ast
+
+import "fmt"
+
+const _Type_name = "TypeInvalidTypeString"
+
+var _Type_index = [...]uint8{0, 11, 21}
+
+func (i Type) String() string {
+	i -= 1
+	if i+1 >= Type(len(_Type_index)) {
+		return fmt.Sprintf("Type(%d)", i+1)
+	}
+	return _Type_name[_Type_index[i]:_Type_index[i+1]]
+}
diff --git a/config/lang/lex_test.go b/config/lang/lex_test.go
index ce6a36960..b5cc7c583 100644
--- a/config/lang/lex_test.go
+++ b/config/lang/lex_test.go
@@ -105,11 +105,3 @@ func TestLex(t *testing.T) {
 		}
 	}
 }
-
-/* OTHERS:
-
-foo ${var.foo}
-bar ${"hello"}
-foo ${concat("foo ${var.bar}", var.baz)}
-
-*/