Angular: ng serve --open return the error "SyntaxError: Use of const in strict mode."

The problem

When you execute:

ng serve --open

You get the following error:

/usr/local/lib/node_modules/@angular/cli/bin/ng:8
const CliConfig = require('../models/config').CliConfig;
^^^^^
SyntaxError: Use of const in strict mode.
    at exports.runInThisContext (vm.js:73:16)
    at Module._compile (module.js:443:25)
    at Object.Module._extensions..js (module.js:478:10)
    at Module.load (module.js:355:32)
    at Function.Module._load (module.js:310:12)
    at Function.Module.runMain (module.js:501:10)
    at startup (node.js:129:16)
    at node.js:814:3

Solution

Check you node version with node -v. Make sure you are using at least version node 6.9.0 and that all angular requirements are met.