New in Rails 7.2: Active Model Got type_for_attribute

What’s New?

Ruby on Rails 7.2 brings a handy change. The type_for_attribute method is now in Active Model.

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What is type_for_attribute?

It’s a method that simplifies type checking, relieving you from the burden of manual checks for both Active Record and Active Model.

How it Works

Here is a simple example:

class MyModel

  include ActiveModel::Attributes

  attribute :my_attribute, :integer


MyModel.type_for_attribute(:my_attribute) # => #<ActiveModel::Type::Integer ...>

Real-Life Example

Think of a signup form. You need to check the types of inputs. Here is how you can use it:

class SignupForm

  include ActiveModel::Attributes

  attribute :email, :string

  attribute :age, :integer

  def initialize(params)

    @params = params

    @params.each do |key, value|

      if self.class.type_for_attribute(key.to_sym)

        send("#{key}=", value)


        raise "Unknown attribute type"





form = "[email protected]", age: "twenty")

# raises "Unknown attribute type" if age is not an integer

Before the Change

Before this update, you had to write custom code. You had to check types manually.

After the Change

Now, type_for_attribute makes it easy and saves you valuable time. Just include ActiveModel::Attributes. It makes your code cleaner and your development process more efficient.

Why It Matters

This change empowers you to catch errors, ensures data integrity, and is a small but powerful tool that puts you in control of your code.

In Summary

Ruby on Rails 7.2 simplifies type checking. Use type_for_attribute with the Active Model. It’s quick and efficient. This change is a great addition. Give it a try in your next project!