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
Lab42::StateMachine.new "my machine" do
state :start do
trigger %r{\A[aeiou]} do |acc, _|
[nil, [acc.first+1, acc.last]]
end
end
endBe aware that a trigger block needs to accept at least one argument
Example: This raises an ArgumentError
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
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: robert.dober@gmail.com
LICENSE
Same as Elixir -- 😉 --, which is Apache License v2.0. Please refer to LICENSE for details.
SPDX-License-Identifier: Apache-2.0