Getting Started 03 Distinguish between development and production environments ("hot update" is performed only in the production environment)

const { src, dest, series, watch, parallel } = require("gulp");function clean(cb) {console.log('clean up dist');cb();}function js(cb){console.log('processing js');cb();}function css(cb){console.log('processing css');cb();}function img(cb){console.log('processing img');cb();}function build(cb) {console.log('Packaging');cb();}function livereload(cb) {console.log('Hot Update');cb();}if (process.env.NODE_ENV === 'production') {exports.default = series(clean,parallel(js,css,img),build);} else {exports.default = series(clean,parallel(js,css,img),build,livereload);}