I have a List of a class where the class is defined like:
case class Role (role_id, elem2, elem3)
well sort of...
so if I have a List of those as roles: List[Role]
how can I get a string of the role_id's so that if my list had 4 Roles in it my string might look like "3 6 8 9" ?
or better still how can i add some string to it so i can get "3, 6, 8, 9" ?
im having to craft some sql and want set based operations instead of looping. I feel i should flatten or something but i cant think
Thank you Martin
Try something like this:
scala> case class Role(role_id: Int, elem2: String, elem3: String)
defined class Role
scala> val l = List(Role(1, "", ""), Role(2, "", ""), Role(3, "", ""))
l: List[Role] = List(Role(1,,), Role(2,,), Role(3,,))
scala> l.map({ case Role(id, _, _) => id }).mkString(", ")
res2: String = 1, 2, 3
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