(* Indexing.def provides a dynamic indexing mechanism.

Copyright (C) 2015-2024 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 Indexing ;

FROM SYSTEM IMPORT ADDRESS ;
EXPORT QUALIFIED Index, InitIndex, KillIndex, GetIndice, PutIndice,
                 HighIndice, LowIndice, InBounds, IsIndiceInIndex,
                 RemoveIndiceFromIndex, IncludeIndiceIntoIndex,
                 ForeachIndiceInIndexDo, DeleteIndice, DebugIndex ;

TYPE
   Index ;
   IndexProcedure = PROCEDURE (ADDRESS) ;


(*
   InitIndex - creates and returns an Index.
*)

PROCEDURE InitIndex (low: CARDINAL) : Index ;


(*
   KillIndex - returns Index to free storage.
*)

PROCEDURE KillIndex (i: Index) : Index ;


(*
   DebugIndex - turns on debugging within an index.
*)

PROCEDURE DebugIndex (i: Index) : Index ;


(*
   InBounds - returns TRUE if indice, n, is within the bounds
              of the dynamic array.
*)

PROCEDURE InBounds (i: Index; n: CARDINAL) : BOOLEAN ;


(*
   HighIndice - returns the last legally accessible indice of this array.
*)

PROCEDURE HighIndice (i: Index) : CARDINAL ;


(*
   LowIndice - returns the first legally accessible indice of this array.
*)

PROCEDURE LowIndice (i: Index) : CARDINAL ;


(*
   PutIndice - places, a, into the dynamic array at position i[n]
*)

PROCEDURE PutIndice (i: Index; n: CARDINAL; a: ADDRESS) ;


(*
   GetIndice - retrieves, element i[n] from the dynamic array.
*)

PROCEDURE GetIndice (i: Index; n: CARDINAL) : ADDRESS ;


(*
   IsIndiceInIndex - returns TRUE if, a, is in the index, i.
*)

PROCEDURE IsIndiceInIndex (i: Index; a: ADDRESS) : BOOLEAN ;


(*
   RemoveIndiceFromIndex - removes, a, from Index, i.
*)

PROCEDURE RemoveIndiceFromIndex (i: Index; a: ADDRESS) ;


(*
   DeleteIndice - delete i[j] from the array.
*)

PROCEDURE DeleteIndice (i: Index; j: CARDINAL) ;


(*
   IncludeIndiceIntoIndex - if the indice is not in the index, then
                            add it at the end.
*)

PROCEDURE IncludeIndiceIntoIndex (i: Index; a: ADDRESS) ;


(*
   ForeachIndiceInIndexDo - for each j indice of i, call procedure p(i[j])
*)

PROCEDURE ForeachIndiceInIndexDo (i: Index; p: IndexProcedure) ;


END Indexing.