Rails adding method to Ruby class issue

Question

I am under:

ruby-1.9.3-p194
Rails 3.0.9

I would like to use in my view method percent_of with Numeric data type.

For example, <%= 10.persent_of(50) %> it's equal 20%.

to do that I have created lib/numeric.rb file that contains

class Numeric
  def percent_of(n)
    self.to_f / n.to_f * 100.0
  end
end

But I got an error:

undefined method `percent_of' for 10:Fixnum

I was trying to add definition require 'Numeric' but it didn't help me.

Help me plz.

You may want to put your file in config/initializers instead. That way you don't need to require it. — Mischa
– Mischa, Commented Aug 2, 2012 at 9:03

Jakob S · Accepted Answer · 2012-08-02 08:47:21Z

1

Try require 'numeric' instead. You're requiring the file, not the class.

answered Aug 2, 2012 at 8:47

Jakob S

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Comments

Syed Aslam · Accepted Answer · 2012-08-02 08:56:24Z

1

Check whether you have config.autoload_paths += %W(#{config.root}/lib) in your application.rb file. You should extend Fixnum instead of Numeric:

class Fixnum
  def percent_of(n)
    self.to_f / n.to_f * 100.0
  end
end

Then require or include this in application_helper.rb so that it is available to all views:

require 'numeric' or include Numeric

answered Aug 2, 2012 at 8:56

Syed Aslam

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