series和 paralle

series 串行执行任务

特性：等待慢的一起输出

const { series } = require('gulp');

function javascript(cb) {
  // body omitted
  cb();
}

function css(cb) {
  // body omitted
  cb();
}

exports.build = series(javascript, css);

paralle 并行执行任务

const { parallel } = require('gulp');

function javascript(cb) {
  // body omitted
  cb();
}

function css(cb) {
  // body omitted
  cb();
}

exports.build = parallel(javascript, css);

优点

避免重复任务

运行组合操作时，每次提供时都会执行每个任务

如果你有这样的代码

const { series, parallel } = require('gulp');

const clean = function(cb) {
  // body omitted
  cb();
};

const css = series(clean, function(cb) {
  // body omitted
  cb();
});

const javascript = series(clean, function(cb) {
  // body omitted
  cb();
});

exports.build = parallel(css, javascript);

改良后

const { series, parallel } = require('gulp');

function clean(cb) {
  // body omitted
  cb();
}

function css(cb) {
  // body omitted
  cb();
}

function javascript(cb) {
  // body omitted
  cb();
}

exports.build = series(clean, parallel(css, javascript));

详情参考网址

https://gulpjs.com/docs/en/api/parallel