Negated blocks

A negated block runs its body when the value is falsy. The opener is {{^name}}; the closer is the same {{/name}} you would use for a positive block:

{{^name}}
You are not logged in
{{/name}}

The body runs when name is null, undefined, false, 0, '', NaN, or an empty array. It is skipped for any truthy value.

Empty arrays

An empty array is falsy in Bigodin (matching the Mustache rule that empty lists are absent). So:

{{^items}}
You have no items.
{{/items}}

…runs over { "items": [] }. The positive form {{#items}}...{{/items}} correctly does not run for empty arrays.

Helpers as negated heads

Like positive blocks, negated blocks can use any helper as their head — most commonly the bundled unless:

{{#unless user.banned}}
  Hello,
  {{user.name}}.
{{else}}
  Access denied.
{{/unless}}

{{#unless x}}...{{else}}...{{/unless}} is functionally {{#if x}}...{{else}}...{{/if}} with the branches swapped. See Block helpers reference.

Literal-named keys

Inside {{# ... }} and {{/ ... }}, the names null, true, false, and undefined are treated as context keys, not as the literal value of the same name:

{{#null}}
This block runs if the context has a key called "null" with a truthy value.
{{/null}}

This matters for templates ported from Mustache where data keys happen to use those names. If you want a conditional against the actual literal null, use the if helper:

{{#if (eq value null)}}value is null{{/if}}

The same rule applies to negated blocks: {{^null}}...{{/null}} looks up the key "null".