Add `readonly`.

dist/types/index.d.ts

@@ -252,9 +252,9 @@ interface ControllerComponent extends BaseComponent {
  * @since 3.0.0
  */
 interface ArrowsComponent extends BaseComponent {
-    arrows: {
-        prev?: HTMLButtonElement;
-        next?: HTMLButtonElement;
+    readonly arrows: {
+        readonly prev?: HTMLButtonElement;
+        readonly next?: HTMLButtonElement;
     };
     /** @internal */
     update(): void;

src/js/components/Arrows/Arrows.ts

@@ -34,7 +34,7 @@ import { PATH, SIZE, XML_NAME_SPACE } from './path';
  * @since 3.0.0
  */
 export interface ArrowsComponent extends BaseComponent {
-  arrows: { prev?: HTMLButtonElement, next?: HTMLButtonElement };
+  readonly arrows: { readonly prev?: HTMLButtonElement, readonly next?: HTMLButtonElement };
 
   /** @internal */
   update(): void;

src/js/components/Elements/Elements.ts

@@ -60,7 +60,7 @@ export interface ElementCollection {
  *
  * @since 3.0.0
  */
-export interface ElementsComponent extends BaseComponent, ElementCollection {
+export interface ElementsComponent extends BaseComponent, Readonly<ElementCollection> {
 }
 
 /**

src/js/components/Pagination/Pagination.ts

@@ -44,7 +44,7 @@ import {
  * @since 3.0.0
  */
 export interface PaginationComponent extends BaseComponent {
-  items: PaginationItem[];
+  readonly items: PaginationItem[];
   getAt( index: number ): PaginationItem;
   update(): void;
 }
@@ -55,8 +55,8 @@ export interface PaginationComponent extends BaseComponent {
  * @since 3.0.0
  */
 export interface PaginationData {
-  list: HTMLUListElement;
-  items: PaginationItem[];
+  readonly list: HTMLUListElement;
+  readonly items: PaginationItem[];
 }
 
 /**
@@ -65,9 +65,9 @@ export interface PaginationData {
  * @since 3.0.0
  */
 export interface PaginationItem {
-  li: HTMLLIElement;
-  button: HTMLButtonElement;
-  page: number;
+  readonly li: HTMLLIElement;
+  readonly button: HTMLButtonElement;
+  readonly page: number;
 }
 
 /**