Cute

An event-centric publisher/subscribe model for objects inspired by the Qt framework and middleware runner.

Installation

Add this to your application's shard.yml:

dependencies:
  cute:
    github: Papierkorb/cute

Usage

See samples/ for more examples.

Signals

Let your user know about an event, without disrupting flow, and without writing some callback code for the umpteenth time. This is a notification mechanism, so the callback (the "slot") has no way of returning something to you. If you need that, see the next section.

See the in-source docs of Cute.signal for further details.

require "cute"

class Button
  Cute.signal clicked(x : Int32, y : Int32)
end

btn = Button.new
btn.clicked.on { |x, y| p x, y }
btn.clicked.emit 5, 4 #=> Will print 5, 4

Middleware

It's easy to allow the user of your library to augment, or otherwise extend, the behaviour of your logic. A middleware works akin to a UNIX pipe, where the input arguments (or the result) can be modified along the call.

See the Cute.middleware in-source docs for further details.

class Chat
  @io : IO = STDOUT

  Cute.middleware def send_message(body : String) : Int32
    @io.puts "Sending #{body}"
    body.size
  end
end

chat = Chat.new

# Add a Capt'n Caps middleware :)
chat.send_message.add { |body, yielder| yielder.call(body.upcase) }

# Send a message
chat.send_message.call("Hello") #=> 5
# Prints "Sending HELLO"

Contributing

1. Fork it ( https://github.com/Papierkorb/cute/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

Contributors

• Papierkorb Stefan Merettig - creator, maintainer