Problem
Attributes in ActiveRecord have no semantic meaning. Validations only describe what to do with a field, not what the field means. But if you know what the field means, then you (and other plugins) can easily infer what to do! So the built-in validations are really tackling the problem backwards.
Solution
Allow the developer to create meaning for ActiveRecord attributes by assigning Predicates in a natural, declarative syntax. Allow the developer (and other plugins) to reflect on predicates and intelligently adapt behavior.
Now that attributes have high-level semantic meaning, you can get other bonus behavior like machine/human formats. Your code needs to deal with normalized or code-like values, but humans need to see something readable. For common patterns (like phone numbers) SemanticAttributes can handle this for you automatically.
Example
class User < ActiveRecord::Base
name_is_required
email_is_required
email_is_an_email :with_mx_record => true
home_page_is_a_url :domains => ['com', 'net', 'org'], :allow_ip_address => false
mobile_is_a_phone_number
end
>> User.name_is_required?
=> true
>> User.mobile_is_required?
=> false
>> User.semantic_attributes[:home_page].get(:url).domains
=> ['com', 'net', 'org']
>> user = User.new
>> user.mobile = '222 333.4444'
>> user.mobile
=> '+12223334444'
>> user.mobile_for_human
=> '(222) 333-4444'Status
Stable, but not ready for public release. It needs to be used by more people than myself before I'm comfortable calling it done.
See Also
Some work has been done in this field already, but the other projects don't seem to realize their entire potential. For comparison, see:
