scope | Daniel P. Clark

April 21, 2016 by Daniel P. Clark

Use Ruby’s Refinements Anywhere With An Anonymous Class

For a long time I’ve been looking for a way to use Ruby’s refinements without building a class & method setup and then instantiating an instance of the class just to use it. And now I’ve finally found a solution.


module Moo
  refine Fixnum do
    def to_s
      "moo"
    end
  end
end

# begin/end blocks allow access to local variables
begin # valid Ruby 2.2.3 and NOT Ruby 2.3.0
  using Moo
  1.to_s
end
# => "moo"

# class syntax has no access to outer local variables
class << Class.new # valid Ruby 2.3.0
  using Moo
  1.to_s
end
# => "moo"

module Moo

refine Fixnum do

def to_s

"moo"

end

# begin/end blocks allow access to local variables

begin # valid Ruby 2.2.3 and NOT Ruby 2.3.0

using Moo

1.to_s

end

# => "moo"

# class syntax has no access to outer local variables

class << Class.new # valid Ruby 2.3.0

using Moo

1.to_s

end

# => "moo"

The best work around I’ve found for accessing values outside the class wood be…

February 2, 2016 by Daniel P. Clark

Ruby: Bindings Across Inheritance

One thing you will find yourself needing to do is work across different scopes and in different ways. I would like to show one way of modifying local variables by passing a Binding object. Let’s say you’re going to write encryption classes and you’ll have different ways of encrypting and decrypting. For these you will have…

March 31, 2015 by Daniel P. Clark

Rails 4’s Awesome enums

In Rails 4 enum was introduced to support a feature that people were building by hand or by gem. What enum does for you is it associates a symbol list for you to reference which will be stored in the database as an integer. So :cow could be 0 and :dog could be 1 in…

January 20, 2015 by Daniel P. Clark

Refinements over Monkey-patching

Monkey patching is rather straight forward. You take an existing object and you apply your own duct tape, glue, nuts and bolts, or even chewing gum. Or if it’s bad you hit it with a hammer. No, but more seriously, it’s when you modify something existing from outside it’s original project code. For example you…