A zero dependency crate to implement state machine.
Let's have a look at the following simple example. This example shows the state machine
can transit its number (it called current_state in this machine)
from given string ("next") and then, it produces outputs.
```rust use statemachine_rs::machine::{builder::StateMachineBuilder, StateMachine};
fn main() { let sm = StateMachineBuilder::start() .initial_state(1) .transition(|state, input| match (state, input) { (1, "next") => 2, (2, "next") => 3, _ => unreachable!(), }) .build() .unwrap();
assert_eq!(1, sm.current_state());
sm.consume("next");
assert_eq!(2, sm.current_state());
} ```
You can assemble your state machine by using statemachine_rs::machine::builder::StateMachineBUilder.
StateMachineBuilder::initial_state() initializes the initial state of its machine.
StateMachineBuilder::transition() defines the transition model.
Of cource we can use enums for representing states and inputs. Let's have a look at another example.
The following example describes if you press the button, the state turns to be On. Otherwise, Off.
```rust use statemachine_rs::machine::{builder::StateMachineBuilder, StateMachine};
enum ButtonState { On, Off, }
enum Input { Press, }
fn main() { let sm = StateMachineBuilder::start() .initial_state(ButtonState::Off) .transition(|state, input| match (state, input) { (ButtonState::On, Input::Press) => ButtonState::Off, (ButtonState::Off, Input::Press) => ButtonState::On, }) .build() .unwrap();
assert_eq!(ButtonState::Off, sm.current_state());
sm.consume(Input::Press);
assert_eq!(ButtonState::On, sm.current_state());
} ```
MIT
All contributions are welcome.
If you have an idea to improve this crate, create new issue or submit new pull request.
License: MIT