Lab42::StateMachine

Usage

The DSL

Define a State Machine by giving it a name and defining states with their transitions in a block:

Example: A Simple Definition

```ruby :example Lab42::StateMachine.new "my machine" do state :start do trigger %r\A[aeiou] do |acc, _| [nil, [acc.first+1, acc.last]] end end end


Be aware that a trigger block needs to accept at least one argument

Example: This raises an ArgumentError

```ruby :example
  machine = 
    Lab42::StateMachine.new "my machine" do
      state :start do
        trigger %r{\A[aeiou]} do
           [nil, nil]
         end
      end
    end
  expect{ machine.run(nil, ["abc"]) }.to raise_error(ArgumentError)

Also there is one state you must not defined, the :stop state

Example: Defining the :stop state

```ruby :example expect do Lab42::StateMachine.new "booom, don't stop" do state :stop do trigger true, :start end end end.to raise_error(FrozenError)







## Author

Copyright © 2020 Robert Dober
mailto: [email protected]

# LICENSE

Same as Elixir -- &#X1F609; --, which is Apache License v2.0. Please refer to [LICENSE](LICENSE) for details.

SPDX-License-Identifier: Apache-2.0