Class: ComposableStateMachine::MachineWithExternalState

Inherits:

Object

• Object
• ComposableStateMachine::MachineWithExternalState

Defined in:

lib/composable_state_machine/machine_with_external_state.rb

Overview

State machine instance that manages its state via a reader and writer objects.

Direct Known Subclasses

Machine

Instance Method Summary

• #==(other_state) ⇒ TrueClass, FalseClass

  Checks whether the state of the machine is equal to another state.

• #initialize(model, state_reader, state_writer, options = {}) ⇒ MachineWithExternalState constructor

  Creates an instance.

• #trigger(event, *args) ⇒ Object^?

  Executes the transition and behaviors associated with an event.

Constructor Details

#initialize(model, state_reader, state_writer, options = {}) ⇒ MachineWithExternalState

Creates an instance.

Parameters:

• model (Model, ...) —

  the model for the machine

• state_reader (Proc, Method, ...) —

  object whose #call method will return the current state

• state_writer (Proc, Method, ...) —

  object whose #call method will be called with the new state after a transition

• options (Hash) (defaults to: {}) —

  the options to create the machine with.

Options Hash (options):

• :state (Object) — default: model#initial_state —

  State of the machine.

• :callback_runner (Object) — default: model#callback_runner —

  Object whose #run_state_machine_callback method will be used to execute behavior callbacks.

# File 'lib/composable_state_machine/machine_with_external_state.rb', line 13

def initialize(model, state_reader, state_writer, options = {})
  @model = model
  @state_reader = state_reader
  @state_writer = state_writer
  @callback_runner = options[:callback_runner] || model.callback_runner
  initial_state = options[:state] || model.initial_state
  @state_writer.call(initial_state)
end

Instance Method Details

#==(other_state) ⇒ TrueClass, FalseClass

Checks whether the state of the machine is equal to another state

Returns:

• (TrueClass, FalseClass)

# File 'lib/composable_state_machine/machine_with_external_state.rb', line 36

def ==(other_state)
  @state_reader.call == other_state
end

#trigger(event, *args) ⇒ Object^?

Executes the transition and behaviors associated with an event.

Parameters:

• event (Object) —

  the event

• args (Array<Object>) —

  event arguments

Returns:

• (Object, nil) —

  the result of model#transition

# File 'lib/composable_state_machine/machine_with_external_state.rb', line 28

def trigger(event, *args)
  current_state = @state_reader.call
  @model.transition(current_state, event, args, @callback_runner, &@state_writer)
end