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-------------------------------------------------------------------------------
-- (C) Altran Praxis Limited
-------------------------------------------------------------------------------
--
-- The SPARK toolset is free software; you can redistribute it and/or modify it
-- under terms of the GNU General Public License as published by the Free
-- Software Foundation; either version 3, or (at your option) any later
-- version. The SPARK toolset 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 distributed with the SPARK toolset; see file
-- COPYING3. If not, go to http://www.gnu.org/licenses for a complete copy of
-- the license.
--
--=============================================================================
--------------------------------------------------------------------------------
-- SimpleLists
--
-- Purpose:
-- Provides an ADT for a bounded, unordered list of Naturals,
-- duplicates permitted. The max size of a list is defined
-- by ExaminerConstants.SimpleListsSize
--
-- Clients:
-- Used by Sem (specifically wf_proc_call) to match lists for formal
-- and actual parameters.
--
-- Use:
-- Declare then Initialize with procedure Init.
--
-- Extension:
-- None planned.
--------------------------------------------------------------------------------
with ExaminerConstants;
--# inherit ExaminerConstants;
package SimpleLists is
type SimpleList is private;
function NumberOfItems (List : SimpleList) return Natural;
procedure Init (List : out SimpleList);
--# derives List from ;
--# post NumberOfItems (List) = 0;
procedure AddItem (Item : in Natural;
List : in out SimpleList;
Ok : out Boolean);
--# derives List from *,
--# Item &
--# Ok from List;
--# post (Ok <-> NumberOfItems (List~) < ExaminerConstants.SimpleListsSize) and
--# (Ok -> NumberOfItems (List) = NumberOfItems (List~) + 1);
procedure GetItem
(List : in SimpleList;
Position : in Positive;
Item : out Natural;
Ok : out Boolean);
--# derives Item,
--# Ok from List,
--# Position;
--# post Ok <-> Position <= NumberOfItems (List);
private
subtype Index is Integer range 0 .. ExaminerConstants.SimpleListsSize;
type ListArrays is array (Index) of Natural;
type SimpleList is record
ListArray : ListArrays;
HighestOccupied : Index;
end record;
end SimpleLists;
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