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, an empty array, or a tagged error returned by a helper. 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".