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class · Ruby 3.0

Module

< Object 74 instance methods 4 class methods

A Module is a collection of methods and constants. The methods in a module may be instance methods or module methods. Instance methods appear as methods in a class when the module is included, module methods do not. Conversely, module methods may be called without creating an encapsulating object, while instance methods may not. (See Module#module_function.)

In the descriptions that follow, the parameter sym refers to a symbol, which is either a quoted string or a Symbol (such as :name).

Example

module Mod
  include Math
  CONST = 1
  def meth
    #  ...
  end
end
Mod.class              #=> Module
Mod.constants          #=> [:CONST, :PI, :E]
Mod.instance_methods   #=> [:meth]

Class methods 4

.constants .nesting .new .used_modules

Instance methods 74

#< #<= #<=> #== #=== #> #>= #alias_method #ancestors #append_features #attr #attr_accessor #attr_reader #attr_writer #autoload #autoload? #class_eval #class_exec #class_variable_defined? #class_variable_get #class_variables #class_variable_set #constants #const_defined? #const_get #const_missing #const_set #const_source_location #define_method #deprecate_constant #extended #extend_object #freeze #include #include? #included #included_modules #inspect #instance_method #instance_methods #method_added #method_defined? #method_removed #method_undefined #module_eval #module_exec #module_function #name #prepend #prepended #prepend_features #private #private_class_method #private_constant #private_instance_methods #private_method_defined? #protected #protected_instance_methods #protected_method_defined? #public #public_class_method #public_constant #public_instance_method #public_instance_methods #public_method_defined? #refine #remove_class_variable #remove_const #remove_method #ruby2_keywords #singleton_class? #to_s #undef_method #using

Ruby version changes 4

3.0
- Module#include and Module#prepend now affect classes and modules that have already included or prepended the receiver, mirroring the behavior if the arguments were included in the receiver before the other modules and classes included or prepended the receiver. [Feature #9573]
  
  Example
```
class C; end
module M1; end
module M2; end
C.include M1
M1.include M2
p C.ancestors #=> [C, M1, M2, Object, Kernel, BasicObject]
```
- Module#public, Module#protected, Module#private, Module#public_class_method, Module#private_class_method, toplevel “private” and “public” methods now accept single array argument with a list of method names. [Feature #17314]
- Module#attr_accessor, Module#attr_reader, Module#attr_writer and Module#attr methods now return an array of defined method names as symbols. [Feature #17314]
- Module#alias_method now returns the defined alias as a symbol. [Feature #17314]