Student or Learner
Which one of the following is correct? What is the rule?
Enter a new name for this control. (The name must be unique.)
Enter a new name for this control (The name must be unique.).
The first. You have two complete sentences.
But why not: Enter a new, unique name for this control.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.