Haml 6 has some breaking changes regarding boolean attributes.

Only the following attributes and aria/data attributes are considered boo...

In the past we validate and set default values for boolean attributes in Rails and not the database itself.

Reasons for this:

• Older Rails didn't s...

We've since created ActiveType which has a restricted subset of Virtus' features. It might be enough for your needs.

We sometimes give our ActiveRecord models [virtual attributes](http://railscasts.c...

This method is defined automatically and only given for boolean attributes

create_table "users", :force => true do |t|
  t.boolean  "email_confirmed"
end

# you may now say:
User.email_confirmed?

tl;dr
You can use attribute? as shorthanded version of attribute.present?, except for numeric attributes and associations.

Technical Details

attribute? is generated for all attributes and not only for boolean attribut...

FactoryBot.define do

  factory :parent do
    transient do
      child_name nil
      child_allowed_to_drive false
    end
    
    child do
      association(:child, name: child_name, allowed_to_drive: child_allowed_to_drive)
    end
  e...

PostgreSQL and ActiveRecord have a good support for storing dynamic attributes (hashes) in columns of type JSONB. But sometimes you are missing some kind of validation or lookup possibility (with plain attributes you can use Active Record's buil...

Haml lets you prefix a group of attributes by wrapping them in a hash. This is only possible with the {} attribute syntax, not with the () attribute syntax.

Example: HTML5 data attributes

HTML5 allows you to use arbitrary attributes like...