Simplest configuration block implementation for a ruby gem ever

For my own gems, I want to have a configuration block, which usually looks like this:

Yourgem.configure do |config|
config.some_config = “foobarbaz”
end

There are a lot of articles how to implement this functionality:
- Ruby Gem Configuration Patterns 
- MyGem.configure Block
- Creating a configurable Ruby gem 
- RubyGem Configuration Pattern 
- The easiest configuration block for your Ruby gems 
- Ruby Gem Configuration Pattern

Isn’t it still looks too complicated? Can’t be a configuration object just a plain ruby hash?

Yes, it can:

module Yourgem
def self.configuration
@configuration ||= {}
end

def self.configure
yield(configuration)
end
end

And now:

Yourgem.configure do |config|
config[:some_config] = "foobarbaz"
end
Yourgem.configuration # => { :some_config => "foobarbaz" }
Yourgem.configuration[:some_config] #=> "foobarbaz"

Looks clean and simple, but there is one restriction: instead of classy Yourgem.configuration.some_config we have to act with it like with hash (because configuration value it’s a hash): Yourgem.configuration[:some_config].

To solve this problem, we will use Ruby’s built-in OpenStruct:

require 'ostruct'
module Yourgem
def self.configuration
@configuration ||= OpenStruct.new
end

def self.configure
yield(configuration)
end
end

And now:

Yourgem.configure do |config|
config.some_config = "foobarbaz"
end
Yourgem.configuration # => #<OpenStruct some_config="foobarbaz">
Yourgem.configuration.some_config #=> "foobarbaz"

Clean and simple.