(* lists.def Provides an unordered list manipulation package.

Copyright (C) 2015-2025 Free Software Foundation, Inc.
Contributed by Gaius Mulley <gaius.mulley@southwales.ac.uk>.

This file is part of GNU Modula-2.

GNU Modula-2 is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.

GNU Modula-2 is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Modula-2; see the file COPYING3.  If not see
<http://www.gnu.org/licenses/>.  *)

DEFINITION MODULE lists ;

FROM SYSTEM IMPORT ADDRESS ;
FROM symbolKey IMPORT performOperation ;

TYPE
   list ;


(*
   initList - creates a new list, l.
*)

PROCEDURE initList () : list ;


(*
   killList - deletes the complete list, l.
*)

PROCEDURE killList (VAR l: list) ;


(*
   putItemIntoList - places an ADDRESS, c, into list, l.
*)

PROCEDURE putItemIntoList (l: list; c: ADDRESS) ;


(*
   getItemFromList - retrieves the nth ADDRESS from list, l.
*)

PROCEDURE getItemFromList (l: list; n: CARDINAL) : ADDRESS ;


(*
   getIndexOfList - returns the index for ADDRESS, c, in list, l.
                    If more than one CARDINAL, c, exists the index
                    for the first is returned.
*)

PROCEDURE getIndexOfList (l: list; c: ADDRESS) : CARDINAL ;


(*
   noOfItemsInList - returns the number of items in list, l.
*)

PROCEDURE noOfItemsInList (l: list) : CARDINAL ;


(*
   includeItemIntoList - adds an ADDRESS, c, into a list providing
                         the value does not already exist.
*)

PROCEDURE includeItemIntoList (l: list; c: ADDRESS) ;


(*
   removeItemFromList - removes an ADDRESS, c, from a list.
                        It assumes that this value only appears once.
*)

PROCEDURE removeItemFromList (l: list; c: ADDRESS) ;


(*
   isItemInList - returns true if a ADDRESS, c, was found in list, l.
*)

PROCEDURE isItemInList (l: list; c: ADDRESS) : BOOLEAN ;


(*
   foreachItemInListDo - calls procedure, P, foreach item in list, l.
*)

PROCEDURE foreachItemInListDo (l: list; p: performOperation) ;


(*
   duplicateList - returns a duplicate list derived from, l.
*)

PROCEDURE duplicateList (l: list) : list ;


END lists.