ActiveModel::AttributeMethods::ClassMethods

alias_attribute(new_name, old_name)

# File activemodel/lib/active_model/attribute_methods.rb, line 223
def alias_attribute(new_name, old_name)
  attribute_method_matchers.each do |matcher|
    matcher_new = matcher.method_name(new_name).to_s
    matcher_old = matcher.method_name(old_name).to_s
    define_optimized_call self, matcher_new, matcher_old
  end
end

attribute_method_affix(*affixes)

Declares a method available for all attributes with the given prefix and suffix. Uses method_missing and respond_to? to rewrite the method.

#{prefix}#{attr}#{suffix}(*args, &block)

to

#{prefix}attribute#{suffix}(#{attr}, *args, &block)

An #{prefix}attribute#{suffix} instance method must exist and accept at least the attr argument.

For example:

class Person

  include ActiveModel::AttributeMethods
  attr_accessor :name
  attribute_method_affix :prefix => 'reset_', :suffix => '_to_default!'
  define_attribute_methods [:name]

  private

  def reset_attribute_to_default!(attr)
    ...
  end
end

person = Person.new
person.name                         # => 'Gem'
person.reset_name_to_default!
person.name                         # => 'Gemma'

Source: show | on GitHub

# File activemodel/lib/active_model/attribute_methods.rb, line 218
def attribute_method_affix(*affixes)
  self.attribute_method_matchers += affixes.map { |affix| AttributeMethodMatcher.new :prefix => affix[:prefix], :suffix => affix[:suffix] }
  undefine_attribute_methods
end

attribute_method_prefix(*prefixes)

Declares a method available for all attributes with the given prefix. Uses method_missing and respond_to? to rewrite the method.

#{prefix}#{attr}(*args, &block)

to

#{prefix}attribute(#{attr}, *args, &block)

An instance method #{prefix}attribute must exist and accept at least the attr argument.

For example:

class Person

  include ActiveModel::AttributeMethods
  attr_accessor :name
  attribute_method_prefix 'clear_'
  define_attribute_methods [:name]

  private

  def clear_attribute(attr)
    send("#{attr}=", nil)
  end
end

person = Person.new
person.name = "Bob"
person.name          # => "Bob"
person.clear_name
person.name          # => nil

Source: show | on GitHub

# File activemodel/lib/active_model/attribute_methods.rb, line 143
def attribute_method_prefix(*prefixes)
  self.attribute_method_matchers += prefixes.map { |prefix| AttributeMethodMatcher.new :prefix => prefix }
  undefine_attribute_methods
end

attribute_method_suffix(*suffixes)

Declares a method available for all attributes with the given suffix. Uses method_missing and respond_to? to rewrite the method.

#{attr}#{suffix}(*args, &block)

to

attribute#{suffix}(#{attr}, *args, &block)

An attribute#{suffix} instance method must exist and accept at least the attr argument.

For example:

class Person

  include ActiveModel::AttributeMethods
  attr_accessor :name
  attribute_method_suffix '_short?'
  define_attribute_methods [:name]

  private

  def attribute_short?(attr)
    send(attr).length < 5
  end
end

person = Person.new
person.name = "Bob"
person.name          # => "Bob"
person.name_short?   # => true

Source: show | on GitHub

# File activemodel/lib/active_model/attribute_methods.rb, line 180
def attribute_method_suffix(*suffixes)
  self.attribute_method_matchers += suffixes.map { |suffix| AttributeMethodMatcher.new :suffix => suffix }
  undefine_attribute_methods
end

define_attribute_method(attr_name)

Source: show | on GitHub

# File activemodel/lib/active_model/attribute_methods.rb, line 259
def define_attribute_method(attr_name)
  attribute_method_matchers.each do |matcher|
    method_name = matcher.method_name(attr_name)

    unless instance_method_already_implemented?(method_name)
      generate_method = "define_method_#{matcher.method_missing_target}"

      if respond_to?(generate_method, true)
        send(generate_method, attr_name)
      else
        define_optimized_call generated_attribute_methods, method_name, matcher.method_missing_target, attr_name.to_s
      end
    end
  end
  attribute_method_matchers_cache.clear
end

define_attribute_methods(attr_names)

Declares the attributes that should be prefixed and suffixed by ActiveModel::AttributeMethods.

To use, pass in an array of attribute names (as strings or symbols), be sure to declare define_attribute_methods after you define any prefix, suffix or affix methods, or they will not hook in.

class Person

  include ActiveModel::AttributeMethods
  attr_accessor :name, :age, :address
  attribute_method_prefix 'clear_'

  # Call to define_attribute_methods must appear after the
  # attribute_method_prefix, attribute_method_suffix or
  # attribute_method_affix declares.
  define_attribute_methods [:name, :age, :address]

  private

  def clear_attribute(attr)
    ...
  end
end

Source: show | on GitHub

# File activemodel/lib/active_model/attribute_methods.rb, line 255
def define_attribute_methods(attr_names)
  attr_names.each { |attr_name| define_attribute_method(attr_name) }
end

undefine_attribute_methods()

Removes all the previously dynamically defined methods from the class

Source: show | on GitHub

# File activemodel/lib/active_model/attribute_methods.rb, line 277
def undefine_attribute_methods
  generated_attribute_methods.module_eval do
    instance_methods.each { |m| undef_method(m) }
  end
  attribute_method_matchers_cache.clear
end

instance_method_already_implemented?(method_name)

Source: show | on GitHub

# File activemodel/lib/active_model/attribute_methods.rb, line 294
def instance_method_already_implemented?(method_name)
  generated_attribute_methods.method_defined?(method_name)
end

Module ActiveModel::AttributeMethods::ClassMethods