Question

I have the following file hierarchy:

Lib > MyModule.rb
Lib > MyModule.rb > MyClass.rb

In MyModule.rb, I have an initialize method:

def initialize(variable, parameter)
  @variable = variable
  @parameter = parameter
end

However, when I try and create an instance of my class, the result is an error:

undefined method: set is not defined for nil

I tried to fix it with this reconstructed version of initialize:

def initialize(variable, parameter)
  @variable = variable
  @parameter = parameter
end

This alleviates the error that I received. However, now I go to create an instance of my class in an HTML.erb file:

<%= MyModule::MyClass.new("string", 1) %>

Here I get an argument error: 2 for 0

Can anyone explain this?

More information as requested:

I’m trying to create a few methods that create html tags as convenience wrappers for commonly used elements. In particular, these utilize the content_tag helper method of rails to create new methods. The plan is eventually to add in nested tag support by using the simple << operator.

Lib/tags.rb

module Tags
  include ActionView::Helpers::TagHelper
  include ActionView::Helpers::JavaScriptHelper
  include ActionView::Context

  def initialize(type, content, options, &block)
    @type = type
    @content = content
    @options = block_given? ? nil : options
    @block = block_given? ? block : nil
  end

  def show
    if @block.nil?
      content_tag(@type, @content, @options)
    else
      content_tag(@type, @content, @options) { @block.call }
    end
  end
end

Now this is the lowest level of the module; these are going to be common to all of the tags that I will be implementing. I then have a class in the Tags folder (Lib/tags/div.rb):

module Tags
  class DivTag
    def initialize(content, options, &block)
      super(:div, content, options, &block)
    end
  end
end

Then in my test file main.rb (which is what is routed to when going to localhost)

And this is where I get my error.

Answer 1

“def Tags” – this is wrong approach, you should use
class Tags …

To call “super” in method – class should be inherited from other class, for example
class DivTag < Tags::Base
def initialize
super() # <- Tags::Base#initialize
end
end

by default every new class inheriting from “Object” class, and Object#initialize accept 0 arguments.

Why you don’t use “content_tag” helper (http://apidock.com/rails/ActionView/Helpers/TagHelper/content_tag) ? Its almost what you want