+++ /dev/null
-class Object
- # Returns +value+ after yielding +value+ to the block. This simplifies the
- # process of constructing an object, performing work on the object, and then
- # returning the object from a method. It is a Ruby-ized realization of the K
- # combinator, courtesy of Mikael Brockman.
- #
- # ==== Examples
- #
- # # Without returning
- # def foo
- # values = []
- # values << "bar"
- # values << "baz"
- # return values
- # end
- #
- # foo # => ['bar', 'baz']
- #
- # # returning with a local variable
- # def foo
- # returning values = [] do
- # values << 'bar'
- # values << 'baz'
- # end
- # end
- #
- # foo # => ['bar', 'baz']
- #
- # # returning with a block argument
- # def foo
- # returning [] do |values|
- # values << 'bar'
- # values << 'baz'
- # end
- # end
- #
- # foo # => ['bar', 'baz']
- def returning(value)
- yield(value)
- value
- end
-
- # Yields <code>x</code> to the block, and then returns <code>x</code>.
- # The primary purpose of this method is to "tap into" a method chain,
- # in order to perform operations on intermediate results within the chain.
- #
- # (1..10).tap { |x| puts "original: #{x.inspect}" }.to_a.
- # tap { |x| puts "array: #{x.inspect}" }.
- # select { |x| x%2 == 0 }.
- # tap { |x| puts "evens: #{x.inspect}" }.
- # map { |x| x*x }.
- # tap { |x| puts "squares: #{x.inspect}" }
- def tap
- yield self
- self
- end unless Object.respond_to?(:tap)
-
- # An elegant way to factor duplication out of options passed to a series of
- # method calls. Each method called in the block, with the block variable as
- # the receiver, will have its options merged with the default +options+ hash
- # provided. Each method called on the block variable must take an options
- # hash as its final argument.
- #
- # with_options :order => 'created_at', :class_name => 'Comment' do |post|
- # post.has_many :comments, :conditions => ['approved = ?', true], :dependent => :delete_all
- # post.has_many :unapproved_comments, :conditions => ['approved = ?', false]
- # post.has_many :all_comments
- # end
- #
- # Can also be used with an explicit receiver:
- #
- # map.with_options :controller => "people" do |people|
- # people.connect "/people", :action => "index"
- # people.connect "/people/:id", :action => "show"
- # end
- #
- def with_options(options)
- yield ActiveSupport::OptionMerger.new(self, options)
- end
-
- # A duck-type assistant method. For example, Active Support extends Date
- # to define an acts_like_date? method, and extends Time to define
- # acts_like_time?. As a result, we can do "x.acts_like?(:time)" and
- # "x.acts_like?(:date)" to do duck-type-safe comparisons, since classes that
- # we want to act like Time simply need to define an acts_like_time? method.
- def acts_like?(duck)
- respond_to? "acts_like_#{duck}?"
- end
-
-end