insane-hook

• InsaneHook

Enjoy the enforcing-DSL of this command-patterny gem.

** Should you use this?

No, you shouldn't. You should write code like this:

#+BEGIN_SRC ruby class MyClassThatDoesSomething def initialize(foo:, bar:) @foo = foo @bar = bar end

def call # do stuff end end #+END_SRC

This code is plain Ruby, everyone can understand it, it doesn't depend on anything. It's way better. You do not need this gem. YOU. DO. NOT. NEED. THIS. GEM.

** Current version

0.5.0

** Installation

Add this line to your application's Gemfile:

#+BEGIN_SRC ruby gem 'insane_hook' #+END_SRC

And then execute:

#+BEGIN_SRC bash $ bundle #+END_SRC

Or install it yourself as:

#+BEGIN_SRC bash $ gem install insane_hook #+END_SRC

** Usage

#+BEGIN_SRC ruby class YeOldeTaske < InsaneHook required :arg1, :arg2 required :arg0 optional :arg3, arg4: 3 optional :arg9 call do # Do some work here # If you really need to return something, even though you shouldn't, leak it: leak "meaningful value" end end #+END_SRC

Is equivalent to:

#+BEGIN_SRC ruby class YeOldeTaske

def self.call(**args)
  new(**args).call
end

attr_reader :arg0, :arg1, :arg2, :arg3, :arg4, :arg9

def initialize(arg0:, arg1:, arg2:, arg3: nil, arg9: nil, arg4: 3)
  @arg0 = arg0
  @arg1 = arg1
  @arg2 = arg2
  @arg3 = arg3
  @arg4 = arg4
  @arg9 = arg9
end

def call
  leak "meaningful value"
  self
end

def leak(arg)
  @_result = arg
end

def result
  if instance_variable_defined?(:@_result)
    @_result
  else
    raise InsaneHook::CommandNotRunError
  end
end

end #+END_SRC

** Design decisions

1. Usage of call is idiomatic Ruby. Procs and method objects respond to call, so we are extending an existing Ruby pattern.
2. Commands should not return anything (they are not queries), but if you are forced to check a result, then set the result to a single object and work off of that object ("leak" that data out of the command).
3. Composition is usually better than Inheritance, especially in a language that doesn't support multiple inheritance. Here we need to use inheritance because we are completely taking over both the .new and the #initialize methods, meaning the object does not truly belong to the person writing the code: the programmer is limited by the provided framework.

** Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

** Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/trevoke/insane_hook.

** License

The gem is available as open source under the terms of the MIT License.