Rule: Disallow `{{unless}}`

Good:

{{#unless somePredicate}}
{{/unless}}

<div class="{{unless foo 'no-foo'}}"></div>

Bad:

{{#unless (and foo bar)}}
{{/unless}}

{{#unless foo}}
{{else}}
{{/unless}}

{{#if foo}}
{{else unless bar}}
{{/if}}

Mostly because it is impossible to reason about…

[cibernox]

I’m actually ok with unless as long as there is no else clause.

[rwjblue]

❤️