ember-cli support for Handlebars @vars in each helper (i.e., @index, @key, @first, @last)

Question

I am getting a compilation error in ember-cli whenever I have a Handelbars template that uses @vars variables (i.e., @index, @key, @first, @last) inside of the each helper.

Answer 1

That really isn't related to ember-cli. Ember Handlebars doesn't support the @keyword items.

Answer 2

It's possible to mimic behavior of following Handlebars keywords: @index, @key, @first, @last.

@index

{{#each array as |item index|}}
  Index of item: `{{item}}` is: `{{index}}`
{{/each}}

@key

{{#each-in object as |key value|}}
  {{key}}: {{value}}
{{/each-in}}

@first

You could also mimic behavior of @first using ember-truth-helpers addon and taking advantage of eq helper - thanks to kristjan reinhold for this idea:

{{#each array as |item index|}}
  {{#if (eq index 0)}}
    <!-- first element specific html -->
  {{else}}
    <!-- other html -->
  {{/if}}
{{/each}}

Instead of (eq index 0) you can use (eq item array.firstObject).

@last

As dwickern suggested you can use Ember.Array.lastObject to mimic @last behavior.

{{#each array as |item|}}
  {{#if (eq item array.lastObject)}}
    <!-- last element specific html -->
  {{else}}
    <!-- other html -->
  {{/if}}
{{/each}}