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docs/javascript_restructure.md

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+## Javascript restructure
+
+### Motivation
+
+A style guide is provided for Javascript in Gov.UK sites at https://github.com/alphagov/govuk-frontend/blob/main/docs/contributing/coding-standards/js.md
+
+Currently the Javascript modules in CCCD do not follow this guide and instead modules are defined in two different ways;
+
+Executing a function expression to return an object;
+
+```javascript
+// app/webpack/javascripts/modules/Helpers.API.Core.js
+
+(function (exports, $) {
+  const Module = exports.Helpers.API || {}
+
+  ...
+
+  Module._CORE = {
+    query
+  }
+
+  exports.Helpers.API = Module
+}(moj, jQuery))
+```
+
+Adding to the `moj` module so that it is initialized together with all modules by `moj.init()` in `app/webpack/javascripts/application.js`;
+
+```javascript
+// app/webpack/javascripts/modules/Helpers.DataTables.js
+
+moj.Helpers.DataTables = {
+  init: function (options, el) {
+    ...
+  },
+
+  ...
+}
+```
+
+The Gov.UK style guide recommends using the class design pattern to structure the code;
+
+```javascript
+class Example {
+  // Code goes here
+}
+```
+
+The primary benefits of refactoring our Javascript is to have a single, consistent style so that future developers can better understand the codebase.
+Specifically using the recommended Gov.UK style will further facilitate new developers who have worked on other Gov.UK projects.
+
+This is a *work in progress* so javascript modules may be written in any of the above formats but the ideal is the class design pattern.