2
# Available in 1.8.6 and later.
3
unless respond_to?(:instance_variable_defined?)
4
def instance_variable_defined?(variable)
5
instance_variables.include?(variable.to_s)
9
# Returns a hash that maps instance variable names without "@" to their
10
# corresponding values. Keys are strings both in Ruby 1.8 and 1.9.
13
# def initialize(x, y)
18
# C.new(0, 1).instance_values # => {"x" => 0, "y" => 1}
19
def instance_values #:nodoc:
20
instance_variables.inject({}) do |values, name|
21
values[name.to_s[1..-1]] = instance_variable_get(name)
26
# Returns an array of instance variable names including "@". They are strings
27
# both in Ruby 1.8 and 1.9.
30
# def initialize(x, y)
35
# C.new(0, 1).instance_variable_names # => ["@y", "@x"]
36
if RUBY_VERSION >= '1.9'
37
def instance_variable_names
38
instance_variables.map { |var| var.to_s }
41
alias_method :instance_variable_names, :instance_variables
44
# Copies the instance variables of +object+ into +self+.
46
# Instance variable names in the +exclude+ array are ignored. If +object+
47
# responds to <tt>protected_instance_variables</tt> the ones returned are
48
# also ignored. For example, Rails controllers implement that method.
50
# In both cases strings and symbols are understood, and they have to include
54
# def initialize(x, y, z)
55
# @x, @y, @z = x, y, z
58
# def protected_instance_variables
66
# a.copy_instance_variables_from(b, [:@y])
67
# # a is now: @x = 3, @y = 1, @z = 2
68
def copy_instance_variables_from(object, exclude = []) #:nodoc:
69
exclude += object.protected_instance_variables if object.respond_to? :protected_instance_variables
71
vars = object.instance_variables.map(&:to_s) - exclude.map(&:to_s)
72
vars.each { |name| instance_variable_set(name, object.instance_variable_get(name)) }