Ruby On Rails: Can I call a class method from a class method?

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I need to know if I can call a class method from a class method and how.

I've got a class on my model and one of my class methods is getting long:

def self.method1(bar)
  # Really long method that I need to split
  # Do things with bar
end

So I want to split this method in 2 methods. Something like that

def self.method1(bar)
  # Do things with bar
  # Call to method2
end

def self.method2(bar)
  # Do things
end

Both of them must be class methods

How can I call this method2 from method1?

Thanks.

This is answered here: Calling a class method within a class

To re-iterate:

def self.method1(bar)
  # Do things with bar
  # Call to method2
  method2( bar )
end

A full class example:

class MyClass
  def self.method1(bar)
    bar = "hello #{ bar }!"
    method2( bar )
  end

  def self.method2(bar)
    puts "bar is #{ bar }"
  end
end

MyClass.method1( 'Foo' )

Ruby On Rails: Can I call a class method from a class method , This post does not concern itself with the “class methods — good or bad? When we call a method upon an object, its singleton class is the first place Ruby will  I need to know if I can call a class method from a class method and how. I've got a class on my model and one of my class methods is getting long: def self.method1(bar) # Really long method that I need to split # Do things with bar end So I want to split this method in 2 methods. Something like that

For you to understand what is going on, you've got to check the scope inside the class method.

class Foo
  def self.bar
    puts self
  end
end

Foo.bar
# => Foo

When Foo.bar is called, Foo is returned. Not an instance, but the class. That means you can access every class method of Foo inside the self.bar method.

class Foo
  def self.bar
    puts "bar was called"
    self.qux
  end

  def self.qux
    puts "qux was called."
  end
end

Foo.bar
# => bar was called
#    qux was called.

Class Methods In Ruby: a Thorough Review & Why I Define Them , Pretty dumb question – how do I call a class method from inside an instance method (of the same class)? The use case I have is that in an  class ClassA def self.method return "This is a method_from_class_A" end end class ClassB def method_calls_method ClassA.method end end instance=ClassB.new puts instance.method_calls_method *Notice the self. in ClassA to signify a class method. This is similar to a static method in other languages.

self in the context of the class method is the class itself. So can access every class method defined in the current class. Examples above are very useful but I want to give you another one which is a little bit more clear (in my opinion):

class MyClass
   def self.method1
     p self
     puts "#{method2}"
   end

   def self.method2
     puts "Hello Ruby World!\n I am class method called from another class method!"
   end
 end

MyClass.method1
# => MyClass

# => Hello Ruby World!
     I am class method called from another class method!

Calling class method from instance method - Ruby, Delegating an instance method to a class method in Ruby creating automated tests, makandra can vastly improve the maintainability of your Rails application. This does something silly but method_missing is an important part of meta-programming in Ruby. In Ruby on Rails it is used extensively to create methods dynamically. Another special methods is initialize that ruby calls whenever a class instance is created, but that belongs in the next chapter: Classes. Conclusion

Delegating an instance method to a class method in Ruby , When defining a class within Ruby, we can also then refer to self within Since this is an instance method, we can't call it until we create a new  Tag: ruby-on-rails,class,model,instance. Is it possible and kosher to use a class method on a model to create a new instance of the same model? The scenario is that I want to interact with an external API, create an instance on the other service, and then once completed successfully store that new object reference in a local model.

Self in Ruby: A Comprehensive Overview, In this edition of Ruby Magic, we'll look at class-level instance to wrap instances of this class with, we can now call the wrap method. On the side, he's writing a book about building SaaS applications in Ruby on Rails. In ruby, classes are also objects, so the methods you define as class methods only exist in the object that defined them (the class) and nowhere else. If you define my_class_method in a class named Test, my_class_method will only live into the object Test, which is an instance of a built-in ruby class named Class.

The Magic of Class-level Instance Variables, What we generally call a class method is a method that resides at the as well as methods that will be local to this object (class methods). Ruby methods are very similar to functions in any other programming language. Ruby methods are used to bundle one or more repeatable statements into a single unit. Method names should begin with a lowercase letter. If you begin a method name with an uppercase letter, Ruby might think that it is a constant and hence can parse the call incorrectly.

Comments
  • Of course you can do this call. Did you try it? Did you get an error? You might need to qualify it with self.: self.method2(bar).
  • If they are inside a class you call normally method2(bar)