From ca9413674ea70dc67ab517734af2e40dac21beef Mon Sep 17 00:00:00 2001 From: Pratik Naik Date: Wed, 26 Mar 2008 12:27:52 +0000 Subject: Improve documentation. git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@9093 5ecf4fe2-1ee6-0310-87b1-e25e094e27de --- .../core_ext/object/instance_variables.rb | 44 ++++++++++++++++++++++ 1 file changed, 44 insertions(+) (limited to 'activesupport/lib/active_support/core_ext/object/instance_variables.rb') diff --git a/activesupport/lib/active_support/core_ext/object/instance_variables.rb b/activesupport/lib/active_support/core_ext/object/instance_variables.rb index 57276135c4..f091acb969 100644 --- a/activesupport/lib/active_support/core_ext/object/instance_variables.rb +++ b/activesupport/lib/active_support/core_ext/object/instance_variables.rb @@ -6,6 +6,16 @@ class Object end end + # Returns a hash that maps instance variable names without "@" to their + # corresponding values. Keys are strings both in Ruby 1.8 and 1.9. + # + # class C + # def initialize(x, y) + # @x, @y = x, y + # end + # end + # + # C.new(0, 1).instance_values # => {"x" => 0, "y" => 1} def instance_values #:nodoc: instance_variables.inject({}) do |values, name| values[name.to_s[1..-1]] = instance_variable_get(name) @@ -13,10 +23,44 @@ class Object end end + # Returns an array of instance variable names including "@". They are strings + # both in Ruby 1.8 and 1.9. + # + # class C + # def initialize(x, y) + # @x, @y = x, y + # end + # end + # + # C.new(0, 1).instance_variable_names # => ["@y", "@x"] def instance_variable_names instance_variables.map(&:to_s) end + # Copies the instance variables of +object+ into self. + # + # Instance variable names in the +exclude+ array are ignored. If +object+ + # responds to protected_instance_variables the ones returned are + # also ignored. For example, Rails controllers implement that method. + # + # In both cases strings and symbols are understood, and they have to include + # the at sign. + # + # class C + # def initialize(x, y, z) + # @x, @y, @z = x, y, z + # end + # + # def protected_instance_variables + # %w(@z) + # end + # end + # + # a = C.new(0, 1, 2) + # b = C.new(3, 4, 5) + # + # a.copy_instance_variables_from(b, [:@y]) + # # a is now: @x = 3, @y = 1, @z = 2 def copy_instance_variables_from(object, exclude = []) #:nodoc: exclude += object.protected_instance_variables if object.respond_to? :protected_instance_variables -- cgit v1.2.3