0.6.0 • Published 1 month ago
fisma v0.6.0
FISMA
What is it
Fisma is a 422b (br,min) finite state _ma_chine that is built on Generators. It features entry/exit actions, events, sending signals to transition to a specific state.
How to use
import { createMachine } from 'fisma';
const m = createMachine([
'A',
{ type: 'B' },
{
type: 'C',
// Add enter and exit
// action as a method
// or array of actions
enter() {},
exit: [() => {}]
},
{
type: 'D',
on: {
RESTART: 'A'
}
},
{
type: 'E',
on: {
RESTART: {
target: 'A',
actions: [ () => console.log('Running actions') ]
}
}
}
]);
// getters
m.current; // A (The active state)
m.done; // false (is the machine running)
// Use `next` to go to the
// next state in array order
m.next();
m.current; // B
// `.subscribe()` returns a cleanup function
const unsub = m.subscribe((ctx) => console.log(ctx));
m.next(); // { type: 'B' }
m.next(); // { type: 'C' }
unsub();
// Pass a string with the
// name of the desired next state
m.next('A');
m.current; // A
m.next('D');
// Signal to the machine a specific
// state to transition to
m.send('RESTART');
m.current; // A
m.next('E');
m.send('RESTART'); // Running actions
m.destroy(); // kills machine
m.done; // true
Things to be aware of
- There isn't a
.start(initialState)
method. The initial state is always the first item in the states array. - While actions are passed a "context" object, currently the context is the active state object and it is not safe to store or alter that information.
active
anddone
might be confusing,active
is for the name of the active state,done
is the status of the machine itself.active
has been changed tocurrent
To Do
- Give a proper "context" object for actions and listeners
- Accept a more complex "requested state" in the
.next()
method - Review method and getter names, e.g.
,active
vs.current
next()
vs.somethingElse()
- Should there be an
initial
getter - Shave bytes