eslint example

esLint

to install eslint run

npm install eslint

create eslint.rc file with contents
{
  "parserOptions": {
    "ecmaVersion": "2018"
  },
  "extends": ["eslint:recommended"],
  "rules": {
    "valid-typeof": "error",  // can be warn, error or off
    "no-console": "off"
  },
  "env": {
    "browser": true
  }
}

run command eslint to show errors