-Prepends I<prefix> followed by a dash I<("-")> to the type instance. See
-B<InstancesFrom> on how the rest of the type instance is built.
+Prepends I<prefix> to the type instance. If B<InstancesFrom> (see below) is not
+given, the string is simply copied. If B<InstancesFrom> is given, I<prefix> and
+all strings returned in the appropriate columns are concatenated together,
+separated by dahes I<("-")>.