Crystal Callback

A Crystal library for defining and invoking callbacks.

Installation

Add this to your application's shard.yml:

dependencies:
  callback:
    github: mosop/callback

Usage

require "callback"

class Record
  Callback.enable
  define_callback_group :save

  before_save do
    puts "before"
  end

  around_save do
    puts "around"
  end

  after_save do
    puts "after"
  end

  on_save do
    puts "on"
  end

  def save
    run_callbacks_for_save do
      puts "yield"
    end
  end
end

rec = Record.new
rec.save

This prints:

before
around
on
yield
around
after

For more detail, see Wiki

Release Notes

• v0.4.0
  • (Breaking Change) Callback.enable no longer receives a class argument. Use Callback.enable inside a class instead.

Contributing

1. Fork it ( https://github.com/mosop/callback/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