state_machine

https://github.com/pluginaweek/state_machine

Ruby

Adds support for creating state machines for attributes on any Ruby class

StateMachine::Machine#write

Sets a new value in the given object's attribute.

For example,

  class Vehicle
    state_machine :initial => :parked do
      ...
    end
  end
  
  vehicle = Vehicle.new                                   # => #<Vehicle:0xb7d94ab0 @state="parked">
  Vehicle.state_machine.write(vehicle, :state, 'idling')  # => Equivalent to vehicle.state = 'idling'
  Vehicle.state_machine.write(vehicle, :event, 'park')    # => Equivalent to vehicle.state_event = 'park'
  vehicle.state                                           # => "idling"
  vehicle.event                                           # => "park"

Source | Google | Stack overflow

Edit

git clone [email protected]:pluginaweek/state_machine.git

cd state_machine

open lib/state_machine/machine.rb

Contribute

# Make a new branch

git checkout -b -your-name--update-docs-StateMachine--Machine-write-for-pr

# Commit to git

git add lib/state_machine/machine.rbgit commit -m "better docs for StateMachine::Machine#write"

# Open pull request

gem install hub # on a mac you can `brew install hub`

hub fork

git push <your name> -your-name--update-docs-StateMachine--Machine-write-for-pr

hub pull-request

# Celebrate!