> is that value of a different type than a foo constructed by X 1.1 I encountered this case once, and they are considered to be different types (in my case the

> is that value of a different type than a foo constructed by X 1.1 I encountered this case once, and they are considered to be different types (in my case the issue was that using v1.0::foo with v1.1::foo traits wouldn't compile), so either keep them separated or pick one. Error messages can be confusing though, if you don't suspect using two versions.