Contents

#!/usr/bin/env ruby

require 'protocol'

Assignable = Protocol do
  def assign_to(assignee)
    Assignee =~ assignee
  end
end

Assignee = Protocol do
end

Assignments = Protocol do
  implementation

  def assignments
    @assignable ||= []
  end

  def add(assignable)
    Assignable =~ assignable
    assignments << assignable
    self
  end

  def assign(assignable, assignee)
    Assignable =~ assignable
    Assignee =~ assignee
    assignable.assign_to(assignee)
    add(assignable)
  end
end

class Task
  def assign_to(assignee)
    @assignee = assignee
  end

  conform_to Assignable
end

class Project
  conform_to Assignments
  conform_to Assignee
end

class User
  conform_to Assignments
  conform_to Assignee
end

p Project.new.assign(Task.new, User.new)
p Project.new.assign(Task.new, Object.new)
begin
  Project.new.assign(Object.new, Task.new)
rescue Protocol::CheckError => e
  p e
end

Version data entries

4 entries across 4 versions & 1 rubygems

Version	Path
protocol-2.0.1	examples/assignments.rb
protocol-2.0.0	examples/assignments.rb
protocol-1.0.1	examples/assignments.rb
protocol-1.0.0	examples/assignments.rb