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------------------------------------------------------------------------------
-- --
-- GNAT LIBRARY COMPONENTS --
-- --
-- A D A . C O N T A I N E R S . F O R M A L _ H A S H E D _ M A P S --
-- --
-- S p e c --
-- --
-- Copyright (C) 2004-2013, Free Software Foundation, Inc. --
-- --
-- This specification is derived from the Ada Reference Manual for use with --
-- GNAT. The copyright notice above, and the license provisions that follow --
-- apply solely to the contents of the part following the private keyword. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 3, or (at your option) any later ver- --
-- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
-- or FITNESS FOR A PARTICULAR PURPOSE. --
-- --
-- As a special exception under Section 7 of GPL version 3, you are granted --
-- additional permissions described in the GCC Runtime Library Exception, --
-- version 3.1, as published by the Free Software Foundation. --
-- --
-- You should have received a copy of the GNU General Public License and --
-- a copy of the GCC Runtime Library Exception along with this program; --
-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
-- <http://www.gnu.org/licenses/>. --
------------------------------------------------------------------------------
-- This spec is derived from package Ada.Containers.Bounded_Hashed_Maps in the
-- Ada 2012 RM. The modifications are meant to facilitate formal proofs by
-- making it easier to express properties, and by making the specification of
-- this unit compatible with SPARK 2014. Note that the API of this unit may be
-- subject to incompatible changes as SPARK 2014 evolves.
-- The modifications are:
-- A parameter for the container is added to every function reading the
-- contents of a container: Key, Element, Next, Query_Element, Has_Element,
-- Iterate, Equivalent_Keys. This change is motivated by the need to have
-- cursors which are valid on different containers (typically a container C
-- and its previous version C'Old) for expressing properties, which is not
-- possible if cursors encapsulate an access to the underlying container.
-- There are four new functions:
-- function Strict_Equal (Left, Right : Map) return Boolean;
-- function Overlap (Left, Right : Map) return Boolean;
-- function First_To_Previous (Container : Map; Current : Cursor)
-- return Map;
-- function Current_To_Last (Container : Map; Current : Cursor)
-- return Map;
-- See detailed specifications for these subprograms
private with Ada.Containers.Hash_Tables;
generic
type Key_Type is private;
type Element_Type is private;
with function Hash (Key : Key_Type) return Hash_Type;
with function Equivalent_Keys (Left, Right : Key_Type) return Boolean;
with function "=" (Left, Right : Element_Type) return Boolean is <>;
package Ada.Containers.Formal_Hashed_Maps is
pragma Annotate (GNATprove, External_Axiomatization);
pragma Pure;
type Map (Capacity : Count_Type; Modulus : Hash_Type) is private with
Iterable => (First => First,
Next => Next,
Has_Element => Has_Element,
Element => Element);
pragma Preelaborable_Initialization (Map);
type Cursor is private;
pragma Preelaborable_Initialization (Cursor);
Empty_Map : constant Map;
No_Element : constant Cursor;
function "=" (Left, Right : Map) return Boolean with
Global => null;
function Capacity (Container : Map) return Count_Type with
Global => null;
procedure Reserve_Capacity
(Container : in out Map;
Capacity : Count_Type)
with
Global => null,
Pre => Capacity <= Container.Capacity;
function Length (Container : Map) return Count_Type with
Global => null;
function Is_Empty (Container : Map) return Boolean with
Global => null;
procedure Clear (Container : in out Map) with
Global => null;
procedure Assign (Target : in out Map; Source : Map) with
Global => null,
Pre => Target.Capacity >= Length (Source);
function Copy
(Source : Map;
Capacity : Count_Type := 0) return Map
with
Global => null,
Pre => Capacity = 0 or else Capacity >= Source.Capacity;
-- Copy returns a container stricty equal to Source. It must have
-- the same cursors associated with each element. Therefore:
-- - capacity=0 means use container.capacity as capacity of target
-- - the modulus cannot be changed.
function Key (Container : Map; Position : Cursor) return Key_Type with
Global => null,
Pre => Has_Element (Container, Position);
function Element
(Container : Map;
Position : Cursor) return Element_Type
with
Global => null,
Pre => Has_Element (Container, Position);
procedure Replace_Element
(Container : in out Map;
Position : Cursor;
New_Item : Element_Type)
with
Global => null,
Pre => Has_Element (Container, Position);
procedure Move (Target : in out Map; Source : in out Map) with
Global => null,
Pre => Target.Capacity >= Length (Source);
procedure Insert
(Container : in out Map;
Key : Key_Type;
New_Item : Element_Type;
Position : out Cursor;
Inserted : out Boolean)
with
Global => null,
Pre => Length (Container) < Container.Capacity;
procedure Insert
(Container : in out Map;
Key : Key_Type;
New_Item : Element_Type)
with
Global => null,
Pre => Length (Container) < Container.Capacity
and then (not Contains (Container, Key));
procedure Include
(Container : in out Map;
Key : Key_Type;
New_Item : Element_Type)
with
Global => null,
Pre => Length (Container) < Container.Capacity;
procedure Replace
(Container : in out Map;
Key : Key_Type;
New_Item : Element_Type)
with
Global => null,
Pre => Contains (Container, Key);
procedure Exclude (Container : in out Map; Key : Key_Type) with
Global => null;
procedure Delete (Container : in out Map; Key : Key_Type) with
Global => null,
Pre => Contains (Container, Key);
procedure Delete (Container : in out Map; Position : in out Cursor) with
Global => null,
Pre => Has_Element (Container, Position);
function First (Container : Map) return Cursor with
Global => null;
function Next (Container : Map; Position : Cursor) return Cursor with
Global => null,
Pre => Has_Element (Container, Position) or else Position = No_Element;
procedure Next (Container : Map; Position : in out Cursor) with
Global => null,
Pre => Has_Element (Container, Position) or else Position = No_Element;
function Find (Container : Map; Key : Key_Type) return Cursor with
Global => null;
function Contains (Container : Map; Key : Key_Type) return Boolean with
Global => null;
function Element (Container : Map; Key : Key_Type) return Element_Type with
Global => null,
Pre => Contains (Container, Key);
function Has_Element (Container : Map; Position : Cursor) return Boolean
with
Global => null;
function Equivalent_Keys
(Left : Map;
CLeft : Cursor;
Right : Map;
CRight : Cursor) return Boolean
with
Global => null;
function Equivalent_Keys
(Left : Map;
CLeft : Cursor;
Right : Key_Type) return Boolean
with
Global => null;
function Equivalent_Keys
(Left : Key_Type;
Right : Map;
CRight : Cursor) return Boolean
with
Global => null;
function Default_Modulus (Capacity : Count_Type) return Hash_Type with
Global => null;
function Strict_Equal (Left, Right : Map) return Boolean with
Global => null;
-- Strict_Equal returns True if the containers are physically equal, i.e.
-- they are structurally equal (function "=" returns True) and that they
-- have the same set of cursors.
function First_To_Previous (Container : Map; Current : Cursor) return Map
with
Global => null,
Pre => Has_Element (Container, Current) or else Current = No_Element;
function Current_To_Last (Container : Map; Current : Cursor) return Map
with
Global => null,
Pre => Has_Element (Container, Current) or else Current = No_Element;
-- First_To_Previous returns a container containing all elements preceding
-- Current (excluded) in Container. Current_To_Last returns a container
-- containing all elements following Current (included) in Container.
-- These two new functions can be used to express invariant properties in
-- loops which iterate over containers. First_To_Previous returns the part
-- of the container already scanned and Current_To_Last the part not
-- scanned yet.
function Overlap (Left, Right : Map) return Boolean with
Global => null;
-- Overlap returns True if the containers have common keys
private
pragma Inline (Length);
pragma Inline (Is_Empty);
pragma Inline (Clear);
pragma Inline (Key);
pragma Inline (Element);
pragma Inline (Contains);
pragma Inline (Capacity);
pragma Inline (Has_Element);
pragma Inline (Equivalent_Keys);
pragma Inline (Next);
type Node_Type is record
Key : Key_Type;
Element : Element_Type;
Next : Count_Type;
Has_Element : Boolean := False;
end record;
package HT_Types is new
Ada.Containers.Hash_Tables.Generic_Bounded_Hash_Table_Types
(Node_Type);
type Map (Capacity : Count_Type; Modulus : Hash_Type) is
new HT_Types.Hash_Table_Type (Capacity, Modulus) with null record;
use HT_Types;
type Cursor is record
Node : Count_Type;
end record;
Empty_Map : constant Map := (Capacity => 0, Modulus => 0, others => <>);
No_Element : constant Cursor := (Node => 0);
end Ada.Containers.Formal_Hashed_Maps;