Creating a Ruby class on the fly without eval

Question

I need to create a Ruby class on the fly, i.e. dynamically which comes from ActiveRecord::Base. I use for evalnow:

eval %Q{
  class ::#{klass} < ActiveRecord::Base
    self.table_name = "#{table_name}"
  end
}

Is there an equivalent and at least as concise way to do this without using eval?

+5

Drtom Jun 11 '12 at 12:46

2 answers

d11wtq · Answer 1 · 2012-06-11T12:48:42+0000

You can use the Class class from which the classes are instances. Not confused yet ?;)

cls = Class.new(ActiveRecord::Base) do
  self.table_name = table_name
end

cls.new

Sergio Tulentsev · Answer 2 · 2012-06-11T12:48:31+0000

Of course have:)

class Foo
  class << self
    attr_accessor :table_name
  end
end

Bar = Class.new(Foo) do
  self.table_name = 'bars'
end

Bar.table_name # => "bars"