Recipe:

Specifying data driven areas of templates that do not need to update


Problem

You have a section of a template that is based on a data but you don’t need the template to update

Solution

Use the {{unbound}} Handlebars helper.

{{unbound firstName}}
{{lastName}}

Discussion

By default all uses of Handlebars helpers in Ember.js will use data bound values that will automatically update the section of the template where a property changes after initial rendering. Ember.Handlebars does this by applying the {{bind}} helper automatically for you.

For example, the two following uses of Handlebars are identical in an Ember.js application:

{{lastName}}
{{bind lastName}}

If you know that a property accessed in Handlebars will not change for the duration of the application’s life, you can specify that the property is not bound by applying the {{unbound}} helper. A property that is not bound will avoid adding unnecessary observers on a property.