src/Pure/Tools/server_commands.scala

       (result_json, (purged, retained))
     }
 
     override val command_body: Server.Command_Body =
       { case (context, Purge_Theories(args)) =>
-        val session = context.server.the_session(args.session_id)
-        command(args, session)._1
+          val session = context.server.the_session(args.session_id)
+          command(args, session)._1
       }
   }
 }
 
 class Server_Commands extends Server.Commands(