composer error - Could not parse version constraint

[plindsay]

When I try to add this to my project via composer I always receive this RuntimeException -

Could not load package mews/purifier in http://repo.packagist.org: [UnexpectedValueException] Could not parse version constraint ~4.*: Invalid version string "~4.*"

I'm not sure how to debug this. Is there a workaround?

Thanks

[plindsay]

For anyone else running into this issue, composer self-update did the trick for me