st8

Tiny state machine for structural describing behavior of components.

Usage

$ npm install st8

Standalone state machine

import State from 'st8';

var state = new State({
    // enter, exit
    b: () => () => {},

    // enter shortcut, forwards to state d
    c: () => 'd',

    // shorter cut, redirects to state a
    d: 'a',

    // any other state
    _: 'a'
});


//enter state 'a', invoke corresponding callbacks
state.set('a');

//get current state
state.get(); // 'a'

Define stateful object property

import State from 'st8'

var state = new State({
    a() {
        // onenter
        this === target //true
    },

    b() {
        // onenter
        this === target //true
        return () => {
            // onexit
        }
    }

}, target);

Object.defineProperty(target, property, {
    set: function (value) {
        return state.set(value);
    },
    get: function () {
        return state.get();
    }
});

API

let state = new State(states [, context])

Create a new state machine based on the states object. Optionally pass a context for callbacks.

state.get()

Get current state.

state.set(value)

Transition to a new state, invoking necessary callbacks.

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