(* wlists.def word lists module.

Copyright (C) 2015-2025 Free Software Foundation, Inc.
Contributed by Gaius Mulley <gaius@glam.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 wlists ;


FROM SYSTEM IMPORT WORD ;

TYPE
   wlist ;
   performOperation = PROCEDURE (WORD) ;


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

PROCEDURE initList () : wlist ;


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

PROCEDURE killList (VAR l: wlist) ;


(*
   putItemIntoList - places an WORD, c, into wlist, l.
*)

PROCEDURE putItemIntoList (l: wlist; c: WORD) ;


(*
   getItemFromList - retrieves the nth WORD from wlist, l.
*)

PROCEDURE getItemFromList (l: wlist; n: CARDINAL) : WORD ;


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

PROCEDURE getIndexOfList (l: wlist; c: WORD) : CARDINAL ;


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

PROCEDURE noOfItemsInList (l: wlist) : CARDINAL ;


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

PROCEDURE includeItemIntoList (l: wlist; c: WORD) ;


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

PROCEDURE removeItemFromList (l: wlist; c: WORD) ;


(*
   replaceItemInList - replace the nth WORD in wlist, l.
                       The first item in a wlists is at index, 1.
                       If the index, n, is out of range nothing is changed.
*)

PROCEDURE replaceItemInList (l: wlist; n: CARDINAL; w: WORD) ;


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

PROCEDURE isItemInList (l: wlist; c: WORD) : BOOLEAN ;


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

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


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

PROCEDURE duplicateList (l: wlist) : wlist ;


END wlists.
