diff options
| -rw-r--r-- | activesupport/lib/active_support/core_ext/class/attribute_accessors.rb | 46 |
1 files changed, 41 insertions, 5 deletions
diff --git a/activesupport/lib/active_support/core_ext/class/attribute_accessors.rb b/activesupport/lib/active_support/core_ext/class/attribute_accessors.rb index 72a918f839..7d85fd512c 100644 --- a/activesupport/lib/active_support/core_ext/class/attribute_accessors.rb +++ b/activesupport/lib/active_support/core_ext/class/attribute_accessors.rb @@ -58,6 +58,42 @@ class Class end end + # Defines a class attribute if it's not defined and creates a writer method to allow + # assignment to the attribute. + # + # class Person + # cattr_writer :hair_colors + # end + # + # Person.hair_colors = [:brown, :black] + # Person.class_variable_get("@@hair_colors") # => [:brown, :black] + # Person.new.hair_colors = [:blonde, :red] + # Person.class_variable_get("@@hair_colors") # => [:blonde, :red] + # + # The attribute name must be any word character starting with a letter or underscore + # and without spaces. + # + # class Person + # cattr_writer :"1_Badname " + # end + # # => NameError: invalid attribute name + # + # If you want to opt out the instance writer method, pass <tt>instance_writer: false</tt> + # or <tt>instance_accessor: false</tt>. + # + # class Person + # cattr_writer :hair_colors, instance_writer: false + # end + # + # Person.new.hair_colors = [:blonde, :red] # => NoMethodError + # + # Also, you can pass a block to set up the variable with a default value. + # + # class Person + # cattr_writer(:hair_colors) {[:brown, :black, :blonde, :red]} + # end + # + # Person.class_variable_get("@@hair_colors") # => [:brown, :black, :blonde, :red] def cattr_writer(*syms) options = syms.extract_options! syms.each do |sym| @@ -103,20 +139,20 @@ class Class # Male.hair_colors << :blue # Person.hair_colors # => [:brown, :black, :blonde, :red, :blue] # - # To opt out of the instance writer method, pass <tt>:instance_writer => false</tt>. - # To opt out of the instance reader method, pass <tt>:instance_reader => false</tt>. + # To opt out of the instance writer method, pass <tt>instance_writer: false</tt>. + # To opt out of the instance reader method, pass <tt>instance_reader: false</tt>. # # class Person - # cattr_accessor :hair_colors, :instance_writer => false, :instance_reader => false + # cattr_accessor :hair_colors, instance_writer: false, instance_reader: false # end # # Person.new.hair_colors = [:brown] # => NoMethodError # Person.new.hair_colors # => NoMethodError # - # Or pass <tt>:instance_accessor => false</tt>, to opt out both instance methods. + # Or pass <tt>instance_accessor: false</tt>, to opt out both instance methods. # # class Person - # cattr_accessor :hair_colors, :instance_accessor => false + # cattr_accessor :hair_colors, instance_accessor: false # end # # Person.new.hair_colors = [:brown] # => NoMethodError |