# ExState 
Elixir [finite state machines](https://en.wikipedia.org/wiki/Finite-state_machine) and [statecharts](http://www.inf.ed.ac.uk/teaching/courses/seoc/2005_2006/resources/statecharts.pdf) library.
- Adheres to the [SCXML specification](https://www.w3.org/TR/scxml/).
- Inspired by [XState JS](https://xstate.js.org/docs/).
## Quick start
### Install
```elixir
def deps do
[
{:ex_state, "~> 2.0.1"}
]
end
```
### Usage
```elixir
iex> definition = %{
iex> id: "toggle",
iex> initial: :inactive,
iex> states: %{
iex> inactive: %{
iex> on: %{
iex> TOGGLE: %{
iex> target: :active
iex> }
iex> }
iex> },
iex> active: %{
iex> on: %{
iex> TOGGLE: %{
iex> target: :inactive
iex> }
iex> }
iex> }
iex> }
iex> }
iex> machine = ExState.machine(definition) # and now create state machine
iex> ExState.transition(machine, :TOGGLE) # and transit to new state
%ExState.Machine{
context: nil,
id: "toggle",
initial: :inactive,
options: %ExState.Options{actions: nil, guards: nil},
state: %ExState.State{
context: nil,
event: %ExState.Event{data: nil, type: :TOGGLE},
value: :active
},
states: %{
active: %ExState.NodeType.Atomic{
on: %{
TOGGLE: %ExState.Transition{actions: [], cond: nil, target: :inactive}
}
},
inactive: %ExState.NodeType.Atomic{
on: %{
TOGGLE: %ExState.Transition{actions: [], cond: nil, target: :active}
}
}
}
}
```
## Statecharts?
Statecharts are a formalism for modeling stateful, reactive systems. This is useful for declaratively describing the behavior of your application, from the individual components to the overall application logic.
- [Statecharts - A Visual Formalism for Complex Systems](http://www.inf.ed.ac.uk/teaching/courses/seoc/2005_2006/resources/statecharts.pdf) by David Harel
- [The World of Statecharts](https://statecharts.github.io/) by Erik Mogensen
- [Pure UI](https://rauchg.com/2015/pure-ui) by Guillermo Rauch
- [Pure UI Control](https://medium.com/@asolove/pure-ui-control-ac8d1be97a8d) by Adam Solove
- [Spectrum - Statecharts Community](https://spectrum.chat/statecharts)
## License
> TODO: Add license
