evt

prepare

run npm install queue-evt --save or yarn add queue-evt

the library include two modules: FnQueue（for handling task queue）and Signal（publish-subscribe）

using in normal html page

<script src="your project path/index.min.js">

using by import or require

import evt from 'evt';
import { FnQueue } from 'evt';

usage: FnQueue

const queue = new evt.FnQueue();

add tasks

queue.add(() => {
    console.log('this is the step0');
    queue.next('the params of step1');
}).add((step1_params) => {
    console.log(step1_params);
});

// the tasks will be performed in sequence
queue.fire();

remove tasks

function step1(step1_params) {
    // ...
}

queue.add(step0 = () => {
    console.log('this is the step0');
    queue.next('the params of step1');
}).add(step1);

queue.remove('step0').remove(step1); // or：queue.remove(['step0', step1]);

skip the task

function step1(step1_params) {
    // ...
}

// the function step1 will not be performed
queue.add(step0 = () => {
    console.log('this is the step0');
    if(Math.floor(Math.random() * 100) % 2 == 0) {
        queue.skip();
    }
}).add(step1);

PS: get into demo folder to view more demo.

usage: Signal

const signal = new evt.Signal();

add a subscription

signal.on('GET_SOME_DATA', function(queue, data) {
    console.log('the data is: ', data);
});

or add a queue of subscriptions

signal.on('GET_SOME_DATA', [
    function(data, queue) {
        console.log('the data is: ', data);
        data.tip = 'hello, this is a tip !';
        queue.next(data);
    },
    function(processed_data, queue) {
        console.log(processed_data);
    }
], {
    autoExcute: false
});

publish a subscription calling 'GET_SOME_DATA'

new Promise(resolve => {
    // emulate to fetching data
    setTimeout(() => {
        resolve({ name: 'Rolling Stone' });
    }, 2000);
}).then(data => {
    signal.emit('GET_SOME_DATA', data);
});