Gulp - issue with 'Task function must be specified'

Question

Example of error as shown below:

$ gulp
assert.js:43
  throw new errors.AssertionError(obj);
  ^

AssertionError [ERR_ASSERTION]: Task function must be specified

 

Commonly it related to gulp version 4.0. 2 options avaiable to fix it:

1. Downgrade your gulp version
   1. Edit your package.json with:

      "gulp": "^3.9.1",
      

   2. Remove your node_modules folder

      rm -rf node_modules
      

   3. And reinstall it by 

      npm i
      

2. Or, update your working code to 4.0