Handlebars helpers

Handlebars supports the idea of helpers, which are special custom functions you can write to perform some special logic from within the template during runtime. This will encourage developers to migrate the common presentation logic present in views into helpers and reuse them, thereby adding much more readability to the views. A great example of a helper would be the date string formatter we've been using. Helpers can be registered globally and made available to every template file, or they can be defined per view and passed to the template on an as-needed basis as part of the viewModel.

Global helpers

First, let's create a global helper that will be available to every Handlebars template we render. The global helper that we will create will be used to format a timestamp so that it is worded according to how long ago the event occurred. We will use this throughout our application for things such as comments and image timestamps.

The first thing we need to do is update our...