alias_method_chain(target, feature) — ActiveSupport::CoreExtensions::Module

alias_method_chain(target, feature)

Encapsulates the common pattern of:

alias_method :foo_without_feature, :foo
alias_method :foo, :foo_with_feature

With this, you simply do:

alias_method_chain :foo, :feature

And both aliases are set up for you.

Query and bang methods (foo?, foo!) keep the same punctuation:

alias_method_chain :foo?, :feature

is equivalent to

alias_method :foo_without_feature?, :foo?
alias_method :foo?, :foo_with_feature?

so you can safely chain foo, foo?, and foo! with the same feature.

Parameters

target req
feature req

Source

# File activesupport/lib/active_support/core_ext/module/aliasing.rb, line 25
      def alias_method_chain(target, feature)
        # Strip out punctuation on predicates or bang methods since
        # e.g. target?_without_feature is not a valid method name.
        aliased_target, punctuation = target.to_s.sub(/([?!=])$/, ''), $1
        yield(aliased_target, punctuation) if block_given?

        with_method, without_method = "#{aliased_target}_with_#{feature}#{punctuation}", "#{aliased_target}_without_#{feature}#{punctuation}"

        alias_method without_method, target
        alias_method target, with_method

        case
          when public_method_defined?(without_method)
            public target
          when protected_method_defined?(without_method)
            protected target
          when private_method_defined?(without_method)
            private target
        end
      end

Defined in activesupport/lib/active_support/core_ext/module/aliasing.rb line 25 · View on GitHub · Improve this page · Find usages on GitHub

Defined in ActiveSupport::CoreExtensions::Module

Signature

Parameters