Composer require vue ^2.0.1

I'm using composer and need vue ^2.0.1. However, I type all this command's and the answer is always:

"Installation failed, reverting ./composer.json to its original content."

The command's are:

composer require vue ^2.0.1 composer require vue "^2.0.1" composer require vue:^2.0.1

What's the correct command?

via Chebli Mohamed