Best practices

{# ✅ CORRECT #}
{% set items = cms.collection('items') %}
{% for item in items %}

{# ❌ INCORRECT #}
{% for item in cms.collection('items') %}  {# Don't load in loop #}

// ✅ CORRECT
options: ['Option 1', 'Option 2', 'Option 3']

// ❌ INCORRECT
options: [{ label: 'Option 1', value: 'option_1' }]

{% if item.status == 'Active' %}  {# Not 'active' - case matters! #}

{# Single file (multiple: false) - direct access as string #}
{{ item.photo }}

{# Multiple files (multiple: true) - array, need loop or index #}
{% for img in item.gallery %}{{ img }}{% endfor %}
{{ item.gallery[0] }}

{# ✅ CORRECT #}
{{ item.content | raw }}

{# ❌ INCORRECT - HTML will be escaped #}
{{ item.content }}

{# ✅ CORRECT #}
{% if item.optional_field is not empty %}
  {{ item.optional_field }}
{% endif %}

{# ❌ INCORRECT - may cause errors #}
{{ item.optional_field }}

{# ✅ CORRECT - Arrow function syntax #}
items | filter(i => i.status == 'Active')

{# ❌ INCORRECT - This won't work in Canvas #}
items | where('status', 'Active')

{# ✅ BETTER - One filter operation #}
{% for category, items in products | group_by('category') %}

{# ❌ LESS EFFICIENT - Filters entire collection multiple times #}
{% set categories = products | column('category')  %}
{% for category in categories %}
  {% for item in products | filter(p => p.category == category) %}

{# ✅ CORRECT #}
${{ price | number_format(2) }}

{# ❌ INCORRECT - may show too many decimals #}
${{ price }}

{# ✅ CORRECT #}
{{ date | date('F jS \\a\\t g:ia') }} {# January 21st at 2:30pm #}

{# ❌ INCORRECT - 'at' will be interpreted as format codes #}
{{ date | date('F jS at g:ia') }} {# Wrong output #}

{# ✅ CORRECT #}
{% for item in items %}
  {{ item.name }}
{% else %}
  <p>No items found</p>
{% endfor %}

{# ❌ INCORRECT - leaves user confused if no items #}
{% for item in items %}
  {{ item.name }}
{% endfor %}