go-mgo/mgo — pull request #2 by FeNoMeNa (2014-07-24 13:41:15+00:00)
Title: Support any type that implements fmt.Stringer in ObjectIdHex and IsObjectIdHex instead of simple string

This change allows using of any type that implements fmt.Stringer in ObjectIdHex and IsObjectIdHex functions.

Example:

If we have type ```type UserId string```, we have to typecast UserId to string.
With this change we simply pass the UserId object without typecast.