feat(ref): make ref return a deeply readonly object

package.json

@@ -60,6 +60,7 @@
   "dependencies": {
     "dbl-linked-list-ds": "^2.0.0",
     "in-node": "^1.0.0",
-    "ts-scheduler": "^8.0.0"
+    "ts-scheduler": "^8.0.0",
+    "utility-types": "^3.7.0"
   }
 }

src/main/Ref.ts

@@ -1,6 +1,7 @@
 /**
  * Created by tushar on 2019-05-25
  */
+import {DeepReadonly} from 'utility-types'
 import {FIO, Task} from './FIO'
 
 export class Ref<A> {
@@ -9,10 +10,10 @@ export class Ref<A> {
   }
   private constructor(private value: A) {}
 
-  public read(): Task<A> {
-    return FIO.try(() => this.value)
+  public read(): Task<DeepReadonly<A>> {
+    return FIO.try(() => this.value as DeepReadonly<A>)
   }
-  public update(ab: (a: A) => A): Task<A> {
-    return FIO.try(() => (this.value = ab(this.value)))
+  public update(ab: (a: DeepReadonly<A>) => A): Task<A> {
+    return FIO.try(() => (this.value = ab(this.value as DeepReadonly<A>)))
   }
 }

yarn.lock

@@ -6281,6 +6281,11 @@ util-extend@^1.0.1:
   resolved "https://registry.yarnpkg.com/util-extend/-/util-extend-1.0.3.tgz#a7c216d267545169637b3b6edc6ca9119e2ff93f"
   integrity sha1-p8IW0mdUUWljeztu3GypEZ4v+T8=
 
+utility-types@^3.7.0:
+  version "3.7.0"
+  resolved "https://registry.yarnpkg.com/utility-types/-/utility-types-3.7.0.tgz#51f1c29fa35d4267488345706efcf3f68f2b1933"
+  integrity sha512-mqRJXN7dEArK/NZNJUubjr9kbFFVZcmF/JHDc9jt5O/aYXUVmopHYujDMhLmLil1Bxo2+khe6KAIVvDH9Yc4VA==
+
 uuid@^3.3.2:
   version "3.3.2"
   resolved "https://registry.yarnpkg.com/uuid/-/uuid-3.3.2.tgz#1b4af4955eb3077c501c23872fc6513811587131"