Modularizing gulp.

copy.js

'use strict';

const gulp = require('gulp');

gulp.task('copy', () => {
    return gulp
        .src('./hello.js')
        .pipe(gulp.dest('./copy/'));
});

gulpfile.js

'use strict';

require('./hello');
require('./copy')

// install gulp globally and locally with `npm i gulp -g & npm i gulp`
// run `gulp -T` to see your tasks

hello.js

'use strict';

const gulp = require('gulp');

gulp.task('hello', () => {
    console.log('Hello, world!');
});