------------------------------------------------------------------------------
--                                                                          --
--                   ASIS-for-GNAT INTERFACE COMPONENTS                     --
--                                                                          --
--                       A S I S . E L E M E N T S                          --
--                                                                          --
--                                 S p e c                                  --
--                                                                          --
--                     Copyright (C) 2006-2016, AdaCore                     --
--                                                                          --
-- This   specification  is  adapted   from  the  Ada   Semantic  Interface --
-- Specification Standard (ISO/IEC 15291) for use with GNAT.  In accordance --
-- with the copyright of that document, you can freely copy and modify this --
-- specification, provided that if you redistribute a modified version, any --
-- changes that you have made are clearly indicated.                        --
--                                                                          --
-- This  specification  also  contains  suggestions  and  discussion  items --
-- related to revising the  ASIS Standard according to the changes proposed --
-- for  the  new  revision of the Ada standard. The copyright notice above, --
-- and the license provisions that follow apply solely to these suggestions --
-- and  discussion  items  that  are separated by the corresponding comment --
-- sentinels                                                                --
--                                                                          --
-- ASIS-for-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 --
-- Software  Foundation;  either version 3,  or (at your option)  any later --
-- version.  ASIS-for-GNAT  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.                     --
--                                                                          --
--                                                                          --
--                                                                          --
--                                                                          --
--                                                                          --
-- You should have  received  a copy of the  GNU General Public License and --
-- a copy of the  GCC Runtime Library Exception  distributed with GNAT; see --
-- the files COPYING3 and COPYING.RUNTIME respectively.  If not, see        --
-- <http://www.gnu.org/licenses/>.                                          --
--                                                                          --
-- ASIS-for-GNAT was originally developed  by the ASIS-for-GNAT team at the --
-- Software  Engineering  Laboratory  of  the Swiss  Federal  Institute  of --
-- Technology (LGL-EPFL) in Lausanne,  Switzerland, in cooperation with the --
-- Scientific  Research  Computer  Center of  Moscow State University (SRCC --
-- MSU), Russia,  with funding partially provided  by grants from the Swiss --
-- National  Science  Foundation  and  the  Swiss  Academy  of  Engineering --
-- Sciences. ASIS-for-GNAT is now maintained by AdaCore                     --
-- (http://www.adacore.com).                                                --
--                                                                          --
------------------------------------------------------------------------------

------------------------------------------------------------------------------
--  13 package Asis.Elements

--  Suggestions related to changing this specification to accept new Ada
--  features as defined in incoming revision of the Ada Standard (ISO 8652)
--  are marked by following comment sentinels:
--
--  --|A2005 start
--   ... the suggestion goes here ...
--  --|A2005 end
--
--  and the discussion items are marked by the comment sentinels of the form:
--
--  --|D2005 start
--   ... the discussion item goes here ...
--  --|D2005 end
--
--  Suggestions related to changing this specification to accept new Ada
--  features as suggested by ARG for next revision of the Ada Standard
--  (ISO 8652) grouped in the end of the package specification.

pragma Ada_2012;

------------------------------------------------------------------------------
------------------------------------------------------------------------------
package Asis.Elements is
------------------------------------------------------------------------------
------------------------------------------------------------------------------
--  Asis.Elements encapsulates a set of queries that operate on all elements
--  and some queries specific to A_Pragma elements.
------------------------------------------------------------------------------
------------------------------------------------------------------------------
--  13.1  function Unit_Declaration
------------------------------------------------------------------------------
--  Gateway queries between Compilation_Units and Elements.
------------------------------------------------------------------------------

   function Unit_Declaration
     (Compilation_Unit : Asis.Compilation_Unit)
      return             Asis.Declaration;

------------------------------------------------------------------------------
--  Compilation_Unit    - Specifies the unit to query
--
--  Returns the element representing the declaration of the compilation_unit.
--
--  Returns a Nil_Element if the unit is A_Nonexistent_Declaration,
--  A_Nonexistent_Body, A_Configuration_Compilation, or An_Unknown_Unit.
--
--  All Unit_Kinds are appropriate except Not_A_Unit.
--
--  Returns Declaration_Kinds:
--       Not_A_Declaration
--       A_Function_Body_Declaration
--       A_Function_Declaration
--       A_Function_Instantiation
--       A_Generic_Function_Declaration
--       A_Generic_Package_Declaration
--       A_Generic_Procedure_Declaration
--       A_Package_Body_Declaration
--       A_Package_Declaration
--       A_Package_Instantiation
--       A_Procedure_Body_Declaration
--       A_Procedure_Declaration
--       A_Procedure_Instantiation
--       A_Task_Body_Declaration
--       A_Package_Renaming_Declaration
--       A_Procedure_Renaming_Declaration
--       A_Function_Renaming_Declaration
--       A_Generic_Package_Renaming_Declaration
--       A_Generic_Procedure_Renaming_Declaration
--       A_Generic_Function_Renaming_Declaration
--       A_Protected_Body_Declaration
--
------------------------------------------------------------------------------
--  13.2  function Enclosing_Compilation_Unit
------------------------------------------------------------------------------

   function Enclosing_Compilation_Unit
     (Element : Asis.Element)
      return    Asis.Compilation_Unit;

------------------------------------------------------------------------------
--  Element - Specifies an Element whose Compilation_Unit is desired
--
--  Returns the Compilation_Unit that contains the given Element.
--
--  Raises ASIS_Inappropriate_Element if the Element is a Nil_Element.
--

------------------------------------------------------------------------------
--  13.3  function Context_Clause_Elements
------------------------------------------------------------------------------

   function Context_Clause_Elements
     (Compilation_Unit : Asis.Compilation_Unit;
      Include_Pragmas  : Boolean := False)
      return             Asis.Context_Clause_List;

------------------------------------------------------------------------------
--  Compilation_Unit - Specifies the unit to query
--  Include_Pragmas  - Specifies whether pragmas are to be returned
--
--  Returns a list of with clauses, use clauses, and pragmas that explicitly
--  appear in the context clause of the compilation unit, in their order of
--  appearance.
--
--  Returns a Nil_Element_List if the unit has A_Nonexistent_Declaration,
--  A_Nonexistent_Body, or An_Unknown_Unit Unit_Kind.
--
--  --|IR
--  All pragma Elaborate elements for this unit will appear in this list. Other
--  pragmas will appear in this list, or in the Compilation_Pragmas list, or
--  both.
--  --|IP
--  Implementors are encouraged to use this list to return all pragmas whose
--  full effect is determined by their exact textual position.  Pragmas that
--  do not have placement dependencies may be returned in either list.  Only
--  pragmas that appear in the unit's context clause are returned
--  by this query.  All other pragmas, affecting the compilation of this
--  unit, are available from the Compilation_Pragmas query.
--
--  Ada predefined packages, such as package Standard, may or may not have
--  context-clause elements available for processing by applications.  The
--  physical existence of a package Standard is implementation specific.
--  The same is true for other Ada predefined packages, such as Ada.Text_Io and
--  Ada.Direct_Io.  The Origin query can be used to determine whether or not
--  a particular unit is an Ada Predefined unit.
--
--  --|IP
--  Results of this query may vary across ASIS implementations.  Some
--  implementations normalize all multi-name with clauses and use clauses
--  into an equivalent sequence of single-name with clause and use clauses.
--  Similarly, an implementation may retain only a single reference to a name
--  that appeared more than once in the original context clause.
--  Some implementors will return only pragma
--  Elaborate elements in this list and return all other pragmas via the
--  Compilation_Pragmas query.
--
--  All Unit_Kinds are appropriate except Not_A_Unit.
--
--  Returns Element_Kinds:
--       A_Pragma
--       A_Clause
--
--  Returns Clause_Kinds:
--       A_With_Clause
--       A_Use_Package_Clause
--
------------------------------------------------------------------------------
--  13.4  function Configuration_Pragmas
------------------------------------------------------------------------------

   function Configuration_Pragmas
     (The_Context : Asis.Context)
      return        Asis.Pragma_Element_List;

------------------------------------------------------------------------------
--  The_Context    - Specifies the Context to query
--
--  Returns a list of pragmas that apply to all future compilation_unit
--  elements compiled into The_Context.  Pragmas returned by this query should
--  have appeared in a compilation that had no compilation_unit elements.
--  To the extent that order is meaningful, the pragmas should be in
--  their order of appearance in the compilation.  (The order is implementation
--  dependent, many pragmas have the same effect regardless of order.)
--
--  Returns a Nil_Element_List if there are no such configuration pragmas.
--
--  Returns Element_Kinds:
--       A_Pragma
--
------------------------------------------------------------------------------
--  13.5  function Compilation_Pragmas
------------------------------------------------------------------------------

   function Compilation_Pragmas
     (Compilation_Unit : Asis.Compilation_Unit)
      return             Asis.Pragma_Element_List;

------------------------------------------------------------------------------
--  Compilation_Unit    - Specifies the unit to query
--
--  Returns a list of pragmas that apply to the compilation of the unit.
--  To the extent that order is meaningful, the pragmas should be in
--  their order of appearance in the compilation.  (The order is implementation
--  dependent, many pragmas have the same effect regardless of order.)
--
--  There are two sources for the pragmas that appear in this list:
--
--   - Program unit pragmas appearing at the place of a compilation_unit.
--     See Reference Manual 10.1.5(4).
--
--   - Configuration pragmas appearing before the first
--     compilation_unit of a compilation.  See Reference Manual 10.1.5(8).
--
--  This query does not return Elaborate pragmas from the unit context
--  clause of the compilation unit; they do not apply to the compilation,
--  only to the unit.
--
--  Use the Context_Clause_Elements query to obtain a list of all pragmas
--  (including Elaborate pragmas) from the context clause of a compilation
--  unit.
--
--  Pragmas from this query may be duplicates of some or all of the
--  non-Elaborate pragmas available from the Context_Clause_Elements query.
--  Such duplication is simply the result of the textual position of the
--  pragma--globally effective pragmas may appear textually within the context
--  clause of a particular unit, and be returned as part of the Context_Clause
--  for that unit.
--
--  Ada predefined packages, such as package Standard, may or may not have
--  pragmas available for processing by applications.  The physical
--  existence of a package Standard is implementation specific.  The same
--  is true for other Ada predefined packages, such as Ada.Text_Io and
--  Ada.Direct_Io. The Origin query can be used to determine whether or
--  not a particular unit is an Ada Predefined unit.
--
--  Returns a Nil_Element_List if the compilation unit:
--
--  - has no such applicable pragmas.
--
--  - is an An_Unknown_Unit, A_Nonexistent_Declaration, or A_Nonexistent_Body.
--
--  - (GNAT-specific) is A_Configuration_Compilation unit.
--
--  All Unit_Kinds are appropriate except Not_A_Unit.
--
--  Returns Element_Kinds:
--       A_Pragma
--
--  GNAT-specific note: In case of GNAT, an ASIS Context is based on so-called
--  tree file. Each tree file may be viewed as a snapshot of a (successful)
--  compilation. All the units involved in a compilation have the same set of
--  compilation pragmas. In case of a Context based on more than one tree file
--  for a unit that has not been compiled on its own to create a tree file, but
--  has been compiled only as a supporter of some other unit, the set of
--  compilation pragmas returned by this query can be computed from any of the
--  compilations (tree files) making up the Context.

------------------------------------------------------------------------------
--  Element_Kinds Hierarchy
------------------------------------------------------------------------------
------------------------------------------------------------------------------
--        Element_Kinds Value      Subordinate Kinds
------------------------------------------------------------------------------
--
--   Key: Read "->" as "can be further categorized by its"
--
--        A_Pragma              -> Pragma_Kinds
--
--        A_Defining_Name       -> Defining_Name_Kinds
--                                         -> Operator_Kinds
--
--        A_Declaration         -> Declaration_Kinds
--                                         -> Declaration_Origin
--                                         -> Mode_Kinds
--                                         -> Subprogram_Default_Kinds
--
--        A_Definition          -> Definition_Kinds
--                                         -> Trait_Kinds
--                                         -> Type_Kinds
--                                         -> Formal_Type_Kinds
--                                         -> Access_Type_Kinds
--                                         -> Root_Type_Kinds
--                                         -> Constraint_Kinds
--                                         -> Discrete_Range_Kinds
--
--        An_Expression         -> Expression_Kinds
--                                         -> Operator_Kinds
--                                         -> Attribute_Kinds
--
--        An_Association        -> Association_Kinds
--
--        A_Statement           -> Statement_Kinds
--
--        A_Path                -> Path_Kinds
--
--        A_Clause              -> Clause_Kinds
--                                         -> Representation_Clause_Kinds
--
--        An_Exception_Handler
--
------------------------------------------------------------------------------
--  13.6  function Element_Kind
------------------------------------------------------------------------------

   function Element_Kind (Element : Asis.Element) return Asis.Element_Kinds;

------------------------------------------------------------------------------
--  Element - Specifies the element to query
--
--  Returns the Element_Kinds value of Element.
--  Returns Not_An_Element for a Nil_Element.
--
--  All element kinds are expected.
--
------------------------------------------------------------------------------
--  13.7  function Pragma_Kind
------------------------------------------------------------------------------
   function Pragma_Kind
     (Pragma_Element : Asis.Pragma_Element)
      return           Asis.Pragma_Kinds;

------------------------------------------------------------------------------
--  Pragma_Element  - Specifies the element to query
--
--  Returns the Pragma_Kinds value of Pragma_Element.
--  Returns Not_A_Pragma for any unexpected element such as a
--  Nil_Element, A_Statement, or A_Declaration.
--
--  Expected Element_Kinds:
--       A_Pragma
--
------------------------------------------------------------------------------
--  13.8  function Defining_Name_Kind
------------------------------------------------------------------------------

   function Defining_Name_Kind
     (Defining_Name : Asis.Defining_Name)
      return          Asis.Defining_Name_Kinds;

------------------------------------------------------------------------------
--  Defining_Name   - Specifies the element to query
--
--  Returns the Defining_Name_Kinds value of the Defining_Name.
--
--  Returns Not_A_Defining_Name for any unexpected element such as a
--  Nil_Element, A_Clause, or A_Statement.
--
--  Expected Element_Kinds:
--       A_Defining_Name
--
------------------------------------------------------------------------------
--  13.9  function Declaration_Kind
------------------------------------------------------------------------------

   function Declaration_Kind
     (Declaration : Asis.Declaration)
      return        Asis.Declaration_Kinds;

------------------------------------------------------------------------------
--  Declaration   - Specifies the element to query
--
--  Returns the Declaration_Kinds value of the Declaration.
--
--  Returns Not_A_Declaration for any unexpected element such as a
--  Nil_Element, A_Definition, or A_Statement.
--
--  Expected Element_Kinds:
--       A_Declaration
--
------------------------------------------------------------------------------
--  13.10 function Trait_Kind
------------------------------------------------------------------------------

   function Trait_Kind (Element : Asis.Element) return Asis.Trait_Kinds;

------------------------------------------------------------------------------
--  Element   - Specifies the Element to query
--
--  Returns the Trait_Kinds value of the Element.
--
--  Returns Not_A_Trait for any unexpected element such as a
--  Nil_Element, A_Statement, or An_Expression.
--
--  Expected Declaration_Kinds:
--      A_Private_Type_Declaration
--      A_Private_Extension_Declaration
--      A_Variable_Declaration
--      A_Constant_Declaration
--      A_Deferred_Constant_Declaration
--      A_Discriminant_Specification
--      A_Loop_Parameter_Specification
--  --|A2012 start
--      A_Generalized_Iterator_Specification
--      An_Element_Iterator_Specification
--  --|A2012 end
--      A_Procedure_Declaration
--      A_Function_Declaration
--      A_Parameter_Specification
--  --|A2005 start
--      A_Return_Object_Declaration
--      An_Object_Renaming_Declaration
--      A_Formal_Object_Declaration
--      A_Formal_Procedure_Declaration
--      A_Formal_Function_Declaration
--  --|A2005 end
--
--  Expected Definition_Kinds:
--      A_Component_Definition
--      A_Private_Type_Definition
--      A_Tagged_Private_Type_Definition
--      A_Private_Extension_Definition
--  --|A2005 start
--      A_Subtype_Indication
--      An_Access_Definition
--  --|A2005 end
--
--  Expected Type_Kinds:
--      A_Derived_Type_Definition
--      A_Derived_Record_Extension_Definition
--      A_Record_Type_Definition
--      A_Tagged_Record_Type_Definition
--  --|A2005 start
--      An_Access_Type_Definition
--  --|A2005 end
--
--  Expected Formal_Type_Kinds:
--      A_Formal_Private_Type_Definition
--      A_Formal_Tagged_Private_Type_Definition
--      A_Formal_Derived_Type_Definition
--
--  --|A2005 start
--  Expected Clause_Kinds:
--      A_With_Clause
--
--  We need a note saying that An_Access_Definition_Trait is an obsolescent
--  value kept only because of upward compatibility reasons. Now an
--  access_definition that defines an anonymous access kind is represented as
--  a first-class citizen in the ASIS Element classification hierarchy
--  (An_Access_Definition value in Definition_Kinds and the subordinate
--  Access_Definition_Kinds type).

--  We have a problem here with A_Discriminant_Specification and
--  A_Parameter_Specification arguments. In Ada 95, the only possible value for
--  them was An_Access_Definition_Trait. Now we do not need this, because we
--  have An_Access_Definition as a new value in Definition_Kinds. But in
--  ASIS 2005 we have to define if the argument is of a new
--  A_Null_Exclusion_Trait Trait_Kinds value. A good thing is that the
--  situations when An_Access_Definition_Trait and A_Null_Exclusion_Trait
--  should be returned do not cross, so we can keep returning the
--  An_Access_Definition_Trait value even though it does not make very much
--  sense for Ada 2005.
--
--  Do we need a special note about this?

--  Another problem is an access definition of the form:
--
--     A : not null access function return not null T;
--     B : not null access function return T;
--     C : access function return not null T;
--
--  We have two null_exclusion syntax elements in the declaration of A, and
--  one null_exclusion syntax element in declarations of B and C, but - in
--  different places. How to make a difference between these cases? We can
--  hardly do this within the Trate_Kinds and with Trate_Kind query. I
--  would add a boolean query Is_Not_Null_Return to represent the presence of
--  null_exclusion in parameter_and_result_profile, and Trait_Kind should
--  reflect only the presence of null_exclusion in the syntax structure
--  of access_definition (this looks logical - an Access_Definition Element
--  represents exactly what is called access_definition in Ada 2005, and
--  we do not have a position in ASIS Elements classification to represent
--  as a whole parameter_and_result_profile or what follows the RETURN
--  keyword in function specification).
--
--  The ARG version of the ASIS 2005 definition says that Trait_Kinds and the
--  corresponding query Trait_Kind are obsolescent. And they are right, because
--  already for Ada 2005 Trait_Kinds cannot describe all the needed variations
--  in Element structure.  The ARG definition suggests the following Boolean
--  queries as the replacement for Trait_Kind(s)

   function Has_Abstract (Element : Asis.Element) return Boolean;
   --  Element specifies the element to query.
   --
   --  Returns True if the reserved word abstract appears in Element, and False
   --  otherwise. Returns False for any unexpected element, including
   --  Nil_Element.
   --
   --  Element expects an element that has one of the following
   --  Declaration_Kinds:
   --     A_Formal_Procedure_Declaration
   --     A_Formal_Function_Declaration
   --     A_Function_Declaration
   --     An_Ordinary_Type_Declaration
   --     A_Private_Type_Declaration
   --     A_Private_Extension_Declaration
   --     A_Procedure_Declaration
   --  or an element that has one of the following Definition_Kinds:
   --     A_Private_Extension_Definition
   --     A_Private_Type_Definition
   --     A_Tagged_Private_Type_Definition
   --     A_Type_Definition
   --  or an element that has one of the following Formal_Type_Kinds:
   --     A_Formal_Private_Type_Definition
   --     A_Formal_Tagged_Private_Type_Definition
   --     A_Formal_Derived_Type_Definition
   --
   --  Note: the specification above is taken "as is" from the ARG ASIS 2005
   --        definition. But there is no sense to include in the list of
   --        expected kinds (that is, to the list of kinds for that the query
   --        can return True) A_Private_Type_Definition and
   --        A_Formal_Private_Type_Definition, because only tagged (formal)
   --        private types can be abstract.

   function Has_Aliased (Element : Asis.Element) return Boolean;
   --  Element specifies the Element to query.
   --
   --  Returns True if the reserved word aliased appears in Element, and False
   --  otherwise. Returns False for any unexpected element, including
   --  Nil_Element.
   --
   --  Element expects an element that has one of the following
   --     Declaration_Kinds:
   --     A_Constant_Declaration
   --     A_Deferred_Constant_Declaration
   --     A_Return_Object_Declaration
   --     A_Variable_Declaration
   --     A_Component_Declaration
   --     A_Parameter_Specification  --  2012
   --  or an element that has the following Definition_Kinds:
   --     A_Component_Definition
   --
   --  NOTES: * A_Component_Declaration is added to the list of expected
   --           Declaration_Kinds given in ARG version of the ASIS 2005
   --           definition.
   --
   --         * A_Parameter_Specification is added to the list of expected
   --           kinds for Ada 2012

   function Has_Limited (Element : Asis.Element) return Boolean;
   --  Element specifies the Element to query.
   --
   --  Returns True if the reserved word limited appears in Element, and False
   --  otherwise. Returns False for any unexpected element, including
   --  Nil_Element.
   --
   --  Element expects an element that has the following Clause_Kinds:
   --     A_With_Clause
   --  or an element that has one of the following Declaration_Kinds:
   --     An_Ordinary_Type_Declaration
   --     A_Private_Type_Declaration
   --     A_Private_Extension_Declaration
   --  or an element that has one of the following Definition_Kinds:
   --     A_Type_Definition
   --     A_Private_Type_Definition
   --     A_Tagged_Private_Type_Definition
   --     A_Private_Extension_Definition
   --  or an element that has one of the following Formal_Type_Kinds:
   --     A_Formal_Private_Type_Definition
   --     A_Formal_Tagged_Private_Type_Definition
   --     A_Formal_Derived_Type_Definition

   function Has_Private (Element : Asis.Element) return Boolean;
   --  Element specifies the element to query.
   --
   --  Returns True if the reserved word private appears in Element, and False
   --  otherwise. Returns False for any unexpected element, including
   --  Nil_Element.
   --
   --  Element expects an element that has one of the following
   --  Declaration_Kinds:
   --     A_Private_Extension_Declaration
   --     A_Private_Type_Declaration
   --  or an element that has one of the following Definition_Kinds:
   --     A_Private_Extension_Definition
   --     A_Private_Type_Definition
   --     A_Tagged_Private_Type_Definition
   --     A_Type_Definition
   --  or an element that has one of the following Formal_Type_Kinds:
   --     A_Formal_Private_Type_Definition
   --     A_Formal_Tagged_Private_Type_Definition
   --  or an element that has the following Clause_Kinds:
   --     A_With_Clause
   --  NOTE: We also support A_Formal_Derived_Type_Definition, because we need
   --  to tell the difference between an non-tagged generic formal derived type
   --  and a generic formal private extension.

   function Has_Protected (Element : Asis.Element) return Boolean;
   --  Element specifies the Element to query.
   --
   --  Returns True if the reserved word protected appears in Element, and
   --  False otherwise. Returns False for any unexpected element, including
   --  Nil_Element.
   --
   --  Element expects an element that has the following Definition_Kinds:
   --     A_Protected_Definition
   --  or an element that has the following Type_Kinds:
   --     An_Interface_Type_Definition
   --  or an element that has one of the following Declaration_Kinds:
   --     A_Protected_Body_Declaration
   --     A_Protected_Type_Declaration
   --     A_Single_Protected_Declaration
   --
   --  NOTE: we have added
   --     A_Protected_Body_Stub
   --  to the list of expected kinds. Should the list of expected kinds also
   --  contain
   --     An_Access_To_Protected_Procedure
   --     An_Access_To_Protected_Function?
   --  At the moment the query returns FALSE for these values.

   function Has_Reverse (Element : Asis.Element) return Boolean;
   --  Element specifies the Element to query.
   --
   --  Returns True if the reserved word reverse appears in Element, and False
   --  otherwise. Returns False for any unexpected element, including
   --  Nil_Element.
   --  Element expects an element that has the following Declaration_Kinds:
   --     A_Loop_Parameter_Specification
   --     A_Generalized_Iterator_Specification
   --     An_Element_Iterator_Specification

   function Has_Synchronized (Element : Asis.Element) return Boolean;
   --  Element specifies the Element to query.
   --
   --  Returns True if the reserved word synchronized appears in Element, and
   --  False otherwise. Returns False for any unexpected element, including
   --  Nil_Element.
   --
   --  Element expects an element that has the following Definition_Kinds:
   --     A_Private_Extension_Definition
   --  or an element that has the following Type_Kinds:
   --     An_Interface_Type_Definition
   --
   --  NOTE: it looks like the following Formal_Type_Kinds value is missing
   --        in the list of expected kinds:
   --
   --           A_Formal_Derived_Type_Definition
   --        According to the syntax defined in 12.5.1 (3/2), it can contain
   --        the reserved word 'synchronized'

   function Has_Tagged (Element : Asis.Element) return Boolean;
   --  Element specifies the Element to query.
   --
   --  Returns True if the reserved word tagged appears in Element, and False
   --  otherwise. Returns False for any unexpected element, including
   --  Nil_Element.
   --
   --  Element expects an element that has one of the following
   --  Definition_Kinds:
   --     A_Tagged_Private_Type_Definition
   --  or an element that has the following Type_Kinds:
   --     A_Tagged_Record_Type_Definition
   --  or an element that has the following Formal_Type_Kinds:
   --     A_Formal_Tagged_Private_Type_Definition
   --  or an element that has the following Declaration_Kinds:
   --     A_Tagged_Incomplete_Type_Declaration
   --     A_Formal_Incomplete_Type_Declaration  (Ada 2012)
   --
   --   NOTE: In the ARG ASIS, the definition of this query contains
   --         A_Tagged_Incomplete_Type_Definition as expected Definition_Kinds
   --         value. But the GNAT ASIS does not have
   --         A_Tagged_Incomplete_Type_Definition, but it has
   --         A_Tagged_Incomplete_Type_Declaration value in Declaration_Kinds
   --         instead. The definition of the query is adjusted to follow GNAT
   --         ASIS.

   function Has_Task (Element : Asis.Element) return Boolean;
   --  Element specifies the Element to query.
   --
   --  Returns True if the reserved word task appears in Element, and False
   --  otherwise. Returns False for any unexpected element, including
   --  Nil_Element.
   --
   --  Element expects an element that has the following Definition_Kinds:
   --     A_Task_Definition
   --  or an element that has the following Type_Kinds:
   --     An_Interface_Type_Definition
   --  or an element that has one of the following Declaration_Kinds:
   --     A_Task_Type_Declaration
   --     A_Single_Task_Declaration
   --     A_Task_Body_Declaration
   --  NOTE: we have added
   --     A_Task_Body_Stub
   --  to the list of expected kinds.

   function Has_Null_Exclusion  --  3.2.2(3/2), 3.7(5/2), 3.10 (2/2,6/2),
                                 --  6.1(13/2,15/2), 8.5.1(2/2), 12.4(2/2)
     (Element : Asis.Element)
      return    Boolean;
   --  Element specifies the element to query.
   --
   --  Returns True if the argument element has a null_exclusion specifier, and
   --  returns False otherwise (including for any unexpected element).
   --
   --  Element expects an element that has one of the following
   --  Definition_Kinds:
   --     A_Type_Definition
   --     An_Access_Definition
   --     A_Subtype_Indication
   --  or Element expects an that has the following Type_Kinds:
   --     An_Access_Type_Definition
   --  or Element expects an that has one of the following Declaration_Kinds:
   --     A_Discriminant_Specification
   --     A_Parameter_Specification
   --     A_Formal_Object_Declaration
   --     An_Object_Renaming_Declaration

--  --|A2005 end

--  --|A2005 start
------------------------------------------------------------------------------
--  13.?? function Is_Not_Null_Return
------------------------------------------------------------------------------

   function Is_Not_Null_Return
     (Element : Asis.Element)
      return    Boolean;

------------------------------------------------------------------------------
--  Element - Specifies the element to check
--
--  Checks if the argument element contains a parameter_and_result_profile
--  component and if this component has null_exclusion specifier
--
--  Returns False for any unexpected element as a Nil_Element, A_Statement or
--  A_Clause.
--
--  Expected Declaration_Kinds:
--       A_Function_Declaration
--       A_Function_Body_Declaration
--       An_Expression_Function_Declaration
--       A_Function_Renaming_Declaration
--       A_Function_Body_Stub
--       A_Generic_Function_Declaration
--       A_Formal_Function_Declaration
--
--  Expected Access_Type_Kinds:  (not implemented in the compiler yet?)
--       An_Access_To_Function
--       An_Access_To_Protected_Function
--
--  Expected Access_Definition_Kinds:  (not implemented in the compiler yet?)
--       An_Anonymous_Access_To_Function
--       An_Anonymous_Access_To_Protected_Function

--  --|A2005 end

--  --|A2005 start
------------------------------------------------------------------------------
--  13.??? function Is_Prefix_Notation (implemented)
------------------------------------------------------------------------------

   function Is_Prefix_Notation (Call : Asis.Element) return Boolean;

------------------------------------------------------------------------------
--  Call - Specifies the procedure or function call to query
--
--  Returns True if the argument is a procedure or a function call in the
--  prefix notation: Object_Name.Operation_Name (...). Returns False for any
--  unexpected argument
--
--  Expected Statement_Kinds:
--       A_Procedure_Call_Statement
--
--  Expected Expression_Kinds:
--       A_Function_Call

--  --|D2005 start
--  What is the right place for this query? Should it be here, should it be
--  in Asis.Statements (with the reference to it in Asis.Expressions or vise
--  versa, or do we need two separate queries - one for procedure calls, and
--  another for function calls
--  --|D2005 end

--  --|A2005 end

------------------------------------------------------------------------------
--  13.11 function Declaration_Origin
------------------------------------------------------------------------------

   function Declaration_Origin
     (Declaration : Asis.Declaration)
      return        Asis.Declaration_Origins;

------------------------------------------------------------------------------
--  Declaration   - Specifies the Declaration to query
--
--  Returns the Declaration_Origins value of the Declaration.
--
--  Returns Not_A_Declaration_Origin for any unexpected element such as a
--  Nil_Element, A_Definition, or A_Clause.
--
--  Expected Element_Kinds:
--       A_Declaration
--
------------------------------------------------------------------------------
--  13.12 function Mode_Kind
------------------------------------------------------------------------------

   function Mode_Kind
     (Declaration : Asis.Declaration)
      return        Asis.Mode_Kinds;

------------------------------------------------------------------------------
--  Declaration   - Specifies the element to query
--
--  Returns the Mode_Kinds value of the Declaration.
--
--  Returns A_Default_In_Mode for an access parameter.
--
--  Returns Not_A_Mode for any unexpected element such as a
--  Nil_Element, A_Definition, or A_Statement.
--
--  Expected Declaration_Kinds:
--       A_Parameter_Specification
--       A_Formal_Object_Declaration
--
------------------------------------------------------------------------------
--  13.13 function Default_Kind
------------------------------------------------------------------------------

   function Default_Kind
     (Declaration : Asis.Generic_Formal_Parameter)
      return        Asis.Subprogram_Default_Kinds;

------------------------------------------------------------------------------
--  Declaration   - Specifies the element to query
--
--  Returns the Subprogram_Default_Kinds value of the Declaration.
--
--  Returns Not_A_Declaration for any unexpected element such as a
--  Nil_Element, A_Definition, or A_Statement.
--
--  Expected Declaration_Kinds:
--       A_Formal_Function_Declaration
--       A_Formal_Procedure_Declaration
--

------------------------------------------------------------------------------
--  13.14 function Definition_Kind
------------------------------------------------------------------------------

   function Definition_Kind
     (Definition : Asis.Definition)
      return       Asis.Definition_Kinds;

------------------------------------------------------------------------------
--  Definition   - Specifies the Definition to query
--
--  Returns the Definition_Kinds value of the Definition.
--
--  Returns Not_A_Definition for any unexpected element such as a
--  Nil_Element, A_Statement, or A_Declaration.
--
--  Expected Element_Kinds:
--       A_Definition
--
------------------------------------------------------------------------------
--  13.15 function Type_Kind
------------------------------------------------------------------------------

   function Type_Kind
     (Definition : Asis.Type_Definition)
      return       Asis.Type_Kinds;

------------------------------------------------------------------------------
--  Definition   - Specifies the Type_Definition to query
--
--  Returns the Type_Kinds value of the Definition.
--
--  Returns Not_A_Type_Definition for any unexpected element such as a
--  Nil_Element, A_Statement, or A_Declaration.
--
--  Expected Definition_Kinds:
--       A_Type_Definition
--
------------------------------------------------------------------------------
--  --|A2005 start (implemented)
--  13.#??? function Access_Definition_Kind
------------------------------------------------------------------------------
   function Access_Definition_Kind
     (Definition : Asis.Definition)
      return       Asis.Access_Definition_Kinds;
------------------------------------------------------------------------------
--  Definition   - Specifies the Definition to query
--
--  Returns the Access_Definition_Kinds value of the Definition.
--
--  Returns Not_An_Access_Definition for any unexpected element such as a
--  Nil_Element, A_Statement, or A_Declaration.
--
--  Expected Definition_Kinds:
--       An_Access_Definition
--
--  --|A2005 end
------------------------------------------------------------------------------
--  13.16 function Formal_Type_Kind
------------------------------------------------------------------------------

   function Formal_Type_Kind
     (Definition : Asis.Formal_Type_Definition)
      return       Asis.Formal_Type_Kinds;

------------------------------------------------------------------------------
--  Definition   - Specifies the Formal_Type_Definition to query
--
--  Returns the Formal_Type_Kinds value of the Definition.
--
--  Returns Not_A_Formal_Type_Definition for any unexpected element such as a
--  Nil_Element, A_Statement, or A_Declaration.
--
--  Expected Definition_Kinds:
--       A_Formal_Type_Definition
--
------------------------------------------------------------------------------
--  13.17 function Access_Type_Kind
------------------------------------------------------------------------------

   function Access_Type_Kind
     (Definition : Asis.Access_Type_Definition)
      return       Asis.Access_Type_Kinds;

------------------------------------------------------------------------------
--  Definition   - Specifies the Access_Type_Definition to query
--
--  Returns the Access_Type_Kinds value of the Definition.
--
--  Returns Not_An_Access_Type_Definition for any unexpected element such as a
--  Nil_Element, A_Statement, or A_Declaration.
--
--  Expected Type_Kinds:
--       An_Access_Type_Definition
--
------------------------------------------------------------------------------
--  --|A2005 start (implemented)
--  13.#??? function Interface_Kind
------------------------------------------------------------------------------
   function Interface_Kind
     (Definition : Asis.Definition)
      return       Asis.Interface_Kinds;
------------------------------------------------------------------------------
--  Definition   - Specifies the Definition to query
--
--  Returns the Interface_Kinds value of the Definition.
--
--  Returns Not_An_Interface for any unexpected element such as a
--  Nil_Element, A_Statement, or A_Declaration.
--
--  Expected Definition_Kinds:
--       A_Type_Definition
--       A_Formal_Type_Definition
--
--  Expected Type_Kinds:
--       An_Interface_Type_Definition
--
--  Expected Formal_Type_Kinds:
--       A_Formal_Interface_Type_Definition
--
--  --|A2005 end
------------------------------------------------------------------------------
--  13.18 function Root_Type_Kind
------------------------------------------------------------------------------

   function Root_Type_Kind
     (Definition : Asis.Root_Type_Definition)
      return       Asis.Root_Type_Kinds;

------------------------------------------------------------------------------
--  Definition   - Specifies the Root_Type_Definition to query
--
--  Returns the Root_Type_Kinds value of the Definition.
--
--  Returns Not_A_Root_Type_Definition for any unexpected element such as a
--  Nil_Element, A_Statement, or A_Declaration.
--
--  Expected Type_Kinds:
--       A_Root_Type_Definition
--
------------------------------------------------------------------------------
--  13.19 function Constraint_Kind
------------------------------------------------------------------------------

   function Constraint_Kind
     (Definition : Asis.Constraint)
      return       Asis.Constraint_Kinds;

------------------------------------------------------------------------------
--  Definition   - Specifies the constraint to query
--
--  Returns the Constraint_Kinds value of the Definition.
--
--  Returns Not_A_Constraint for any unexpected element such as a
--  Nil_Element, A_Statement, or A_Declaration.
--
--  Expected Definition_Kinds:
--       A_Constraint
--
------------------------------------------------------------------------------
--  13.20 function Discrete_Range_Kind
------------------------------------------------------------------------------

   function Discrete_Range_Kind
     (Definition : Asis.Discrete_Range)
      return       Asis.Discrete_Range_Kinds;

------------------------------------------------------------------------------
--  Definition   - Specifies the discrete_range to query
--
--  Returns the Discrete_Range_Kinds value of the Definition.
--
--  Returns Not_A_Discrete_Range for any unexpected element such as a
--  Nil_Element, A_Statement, or A_Declaration.
--
--  Expected Definition_Kinds:
--       A_Discrete_Subtype_Definition
--       A_Discrete_Range
--

------------------------------------------------------------------------------
--  13.21 function Expression_Kind
------------------------------------------------------------------------------

   function Expression_Kind
     (Expression : Asis.Expression)
      return       Asis.Expression_Kinds;

------------------------------------------------------------------------------
--  Expression   - Specifies the Expression to query
--
--  Returns the Expression_Kinds value of the Expression.
--
--  Returns Not_An_Expression for any unexpected element such as a
--  Nil_Element, A_Statement, or A_Declaration.
--
--  Expected Element_Kinds:
--       An_Expression
--
------------------------------------------------------------------------------
--  13.22 function Operator_Kind
------------------------------------------------------------------------------

   function Operator_Kind
     (Element : Asis.Element)
      return    Asis.Operator_Kinds;

------------------------------------------------------------------------------
--  Element   - Specifies the Element to query
--
--  Returns the Operator_Kinds value of the A_Defining_Name or An_Expression
--  element.
--
--  Returns Not_An_Operator for any unexpected element such as a
--  Nil_Element, A_Statement, or A_Declaration.
--
--  Expected Defining_Name_Kinds:
--       A_Defining_Operator_Symbol
--
--  Expected Expression_Kinds:
--       An_Operator_Symbol
--
------------------------------------------------------------------------------
--  13.23 function Attribute_Kind
------------------------------------------------------------------------------

   function Attribute_Kind
     (Expression : Asis.Expression)
      return       Asis.Attribute_Kinds;

------------------------------------------------------------------------------
--  Expression   - Specifies the Expression to query
--
--  Returns the Attribute_Kinds value of the Expression.
--
--  Returns Not_An_Attribute for any unexpected element such as a
--  Nil_Element, A_Statement, or A_Declaration.
--
--  Expected Expression_Kinds:
--       An_Attribute_Reference
--
------------------------------------------------------------------------------
--  13.24 function Association_Kind
------------------------------------------------------------------------------

   function Association_Kind
     (Association : Asis.Association)
      return        Asis.Association_Kinds;

------------------------------------------------------------------------------
--  Association   - Specifies the Association to query
--
--  Returns the Association_Kinds value of the Association.
--

--  Returns Not_An_Association for any unexpected element such as a
--  Nil_Element, A_Statement, or A_Declaration.
--
--  Expected Element_Kinds:
--       An_Association
--
------------------------------------------------------------------------------
--  13.25 function Statement_Kind
------------------------------------------------------------------------------

   function Statement_Kind
     (Statement : Asis.Statement)
      return      Asis.Statement_Kinds;

------------------------------------------------------------------------------
--  Statement   - Specifies the element to query
--
--  Returns the Statement_Kinds value of the statement.
--
--  Returns Not_A_Statement for any unexpected element such as a
--  Nil_Element, A_Definition, or A_Declaration.
--
--  Expected Element_Kinds:
--       A_Statement
--
------------------------------------------------------------------------------
--  13.26 function Path_Kind
------------------------------------------------------------------------------

   function Path_Kind (Path : Asis.Path) return Asis.Path_Kinds;

------------------------------------------------------------------------------
--  Path   - Specifies the Path to query
--
--  Returns the Path_Kinds value of the Path.
--
--  Returns Not_A_Path for any unexpected element such as a
--  Nil_Element, A_Statement, or A_Declaration.
--
--  Expected Element_Kinds:
--       A_Path
--
------------------------------------------------------------------------------
--  13.27 function Clause_Kind
------------------------------------------------------------------------------

   function Clause_Kind (Clause : Asis.Clause) return Asis.Clause_Kinds;

------------------------------------------------------------------------------
--  Clause   - Specifies the element to query
--
--  Returns the Clause_Kinds value of the Clause.
--
--  Returns Not_A_Clause for any unexpected element such as a
--  Nil_Element, A_Definition, or A_Declaration.
--
--  Expected Element_Kinds:
--       A_Clause
--
------------------------------------------------------------------------------
--  13.28 function Representation_Clause_Kind
------------------------------------------------------------------------------

   function Representation_Clause_Kind
     (Clause : Asis.Representation_Clause)
      return   Asis.Representation_Clause_Kinds;

------------------------------------------------------------------------------
--  Clause   - Specifies the element to query
--
--  Returns the Representation_Clause_Kinds value of the Clause.
--
--  Returns Not_A_Representation_Clause for any unexpected element such as a
--  Nil_Element, A_Definition, or A_Declaration.
--
--  Expected Clause_Kinds:
--       A_Representation_Clause
--
------------------------------------------------------------------------------
--  13.29 function Is_Nil
------------------------------------------------------------------------------

   function Is_Nil (Right : Asis.Element) return Boolean;

------------------------------------------------------------------------------
--  Right   - Specifies the element to check
--
--  Returns True if the program element is the Nil_Element.
--
------------------------------------------------------------------------------
--  13.30 function Is_Nil
------------------------------------------------------------------------------

   function Is_Nil (Right : Asis.Element_List) return Boolean;

------------------------------------------------------------------------------
--  Right   - Specifies the element list to check
--
--  Returns True if the element list has a length of zero.
--
------------------------------------------------------------------------------
--  13.31 function Is_Equal
------------------------------------------------------------------------------

   function Is_Equal
     (Left  : Asis.Element;
      Right : Asis.Element)
      return  Boolean;

------------------------------------------------------------------------------
--  Left    - Specifies the left element to compare
--  Right   - Specifies the right element to compare
--
--  Returns True if Left and Right represent the same physical element,
--  from the same physical compilation unit.  The two elements may or
--  may not be from the same open ASIS Context variable.
--
--  Implies: Is_Equal (Enclosing_Compilation_Unit (Left),
--                     Enclosing_Compilation_Unit (Right)) = True
--
------------------------------------------------------------------------------
--  13.32 function Is_Identical
------------------------------------------------------------------------------

   function Is_Identical
     (Left  : Asis.Element;
      Right : Asis.Element)
      return  Boolean;

------------------------------------------------------------------------------
--  Left    - Specifies the left element
--  Right   - Specifies the right element
--
--  Returns True if Left and Right represent the same physical element,
--  from the same physical compilation unit, from the same open ASIS
--  Context variable.
--
--  Implies: Is_Identical (Enclosing_Compilation_Unit (Left),
--                         Enclosing_Compilation_Unit (Right)) = True
--

------------------------------------------------------------------------------
--  13.33 function Is_Part_Of_Implicit
------------------------------------------------------------------------------

   function Is_Part_Of_Implicit (Element : Asis.Element) return Boolean;

------------------------------------------------------------------------------
--  Element - Specifies the element to query
--
--  Returns True for any Element that is, or that forms part of, any
--  implicitly declared or specified program Element structure.
--
--  Returns False for a Nil_Element, or any Element that correspond to text
--  which was specified explicitly (typed, entered, written).
--
--  Generic instance specifications and bodies, while implicit, are treated
--  as a special case.  These elements will not normally test as
--  Is_Part_Of_Implicit.  Rather, they are Is_Part_Of_Instance.  They only test
--  as Is_Part_Of_Implicit if one of the following rules applies.  This is
--  done so that it is possible to determine whether a declaration, which
--  happens to occur within an instance, is an implicit result of
--  another declaration which occurs explicitly within the generic template.
--
--  Implicit Elements are those that represent these portions of the Ada
--  language:
--
--  Reference Manual 4.5.(9)    - All predefined operator declarations and
--                                their component elements are
--                                Is_Part_Of_Implicit
--  Reference Manual 3.4(16)    - Implicit predefined operators of the derived
--                                type.
--  Reference Manual 3.4(17-22) - Implicit inherited subprogram declarations
--                                and their component elements are
--                                Is_Part_Of_Implicit
--
--  Reference Manual 6.4(9)     - Implicit actual parameter expressions
--                                (defaults).
--              and 12.3(7)     - The A_Parameter_Association that includes a
--                                defaulted parameter value Is_Normalized and
--                                also Is_Part_Of_Implicit. The
--                                Formal_Parameter and the Actual_Parameter
--                                values from such Associations are not
--                                Is_Part_Of_Implicit unless they are from
--                                default initializations for an inherited
--                                subprogram declaration and have an
--                                Enclosing_Element that is the parameter
--                                specification of the subprogram declaration.
--                                (Those elements are shared with (were created
--                                by) the original subprogram declaration, or
--                                they are naming expressions representing the
--                                actual generic subprogram selected at the
--                                place of an instantiation for A_Box_Default.)
--                              - All A_Parameter_Association Kinds from a
--                                Normalized list are Is_Part_Of_Implicit.
--
--  Reference Manual 6.6 (6)    - Inequality operator declarations for limited
--                                private types are Is_Part_Of_Implicit.
--                              - Depending on the ASIS implementation, a "/="
--                                appearing in the compilation may result in a
--                                "NOT" and an "=" in the internal
--                                representation.  These two elements test as
--                                Is_Part_Of_Implicit because they do not
--                                represent text from the original compilation
--                                text.
--  Reference Manual 12.3 (16)  - implicit generic instance specifications and
--                                bodies are not Is_Part_Of_Implicit; they are
--                                Is_Part_Of_Instance and are only implicit if
--                                some other rule makes them so
--
------------------------------------------------------------------------------
--  13.34 function Is_Part_Of_Inherited
------------------------------------------------------------------------------

   function Is_Part_Of_Inherited (Element : Asis.Element) return Boolean;

------------------------------------------------------------------------------
--  Element - Specifies the element to query
--
--  Returns True for any Element that is, or that forms part of, an
--  inherited primitive subprogram declaration.
--
--  Returns False for any other Element including a Nil_Element.
--
------------------------------------------------------------------------------
--  13.35 function Is_Part_Of_Instance
------------------------------------------------------------------------------

   function Is_Part_Of_Instance (Element : Asis.Element) return Boolean;

------------------------------------------------------------------------------
--  Element - Specifies the element to test
--
--  Returns True if the Element is part of an implicit generic specification
--  instance or an implicit generic body instance.
--
--  Returns False for explicit, inherited, and predefined Elements that are
--  not the result of a generic expansion.
--
--  Returns False for a Nil_Element.
--
--  Instantiations are not themselves Is_Part_Of_Instance unless they are
--  encountered while traversing a generic instance.
--
------------------------------------------------------------------------------
--  13.36 function Enclosing_Element
------------------------------------------------------------------------------

   function Enclosing_Element (Element : Asis.Element) return Asis.Element;

   function Enclosing_Element
     (Element                    : Asis.Element;
      Expected_Enclosing_Element : Asis.Element)
      return                       Asis.Element;

------------------------------------------------------------------------------
--  Element - Specifies the element to query
--  Expected_Enclosing_Element - Specifies an enclosing element expected to
--  contain the element
--
--  Returns the Element that immediately encloses the given element.  This
--  query is intended to exactly reverse any single parent-to-child element
--  traversal.  For any structural query that returns a subcomponent of an
--  element (or that returns a list of subcomponent elements), the original
--  element can be determined by passing the subcomponent element to this
--  query.
--  Note: Semantic queries (queries that test the meaning of a program rather
--  than its structure) return Elements that usually do not have the original
--  argument Element as their parent.
--
--  Returns a Nil_Element if:
--
--   - the element is the declaration part of a compilation unit
--     (Unit_Declaration).
--
--   - the element is with clause or use clause of a context clause
--     (Context_Clause_Elements).
--
--   - the element is a pragma for a compilation unit
--     (Compilation_Pragmas and Context_Clause_Elements).
--
--  Use Enclosing_Compilation_Unit to get the enclosing compilation unit for
--  any element value other than Nil_Element.
--
--  Raises ASIS_Inappropriate_Element if the Element is a Nil_Element.
--
--  Examples:
--
--    Given a A_Declaration/A_Full_Type_Declaration in the declarative region
--    of a block statement, returns the A_Statement/A_Block_Statement Element
--    that encloses the type declaration.
--
--    Given A_Statement, from the sequence of statements within a loop
--    statement, returns the enclosing A_Statement/A_Loop_Statement.
--
--    Given the An_Expression/An_Identifier selector from an expanded name,
--    returns the An_Expression/A_Selected_Component that represents the
--    combination of the prefix, the dot, and the selector.
--
--  --|AN Application Note:
--  --|AN
--  --|AN The optional Expected_Enclosing_Element parameter is used only to
--  --|AN optimize. This speed up is only present for ASIS implementations
--  --|AN where the underlying implementor's environment does not have "parent
--  --|AN pointers". For these implementations, this query is implemented as a
--  --|AN "search". The Enclosing_Compilation_Unit is searched for the argument
--  --|AN Element. The Expected_Enclosing_Element parameter provides a means of
--  --|AN shortening the search.
--  --|AN Note: If the argument Element is not a sub-element of the
--  --|AN Expected_Enclosing_Element parameter, or if the
--  --|AN Expected_Enclosing_Element is a Nil_Element, the result of the
--  --|AN call is a Nil_Element.
--  --|AN
--  --|AN Implementations that do not require the Expected_Enclosing_Element
--  --|AN parameter may ignore it.  They are encouraged, but not required, to
--  --|AN test the Expected_Enclosing_Element parameter and to determine if it
--  --|AN is an invalid Element value (its associated Environment Context may
--  --|AN be closed)
--  --|AN
--  --|AN Portable applications should not use the Expected_Enclosing_Element
--  --|AN parameter since it can lead to unexpected differences when porting an
--  --|AN application between ASIS implementations where one implementation
--  --|AN uses the parameter and the other implementation does not. Passing a
--  --|AN "wrong" Expected_Enclosing_Element to an implementation that ignores
--  --|AN it, is harmless. Passing a "wrong" Expected_Enclosing_Element to an
--  --|AN implementation that may utilize it, can lead to an unexpected
--  --|AN Nil_Element result.
--  --
------------------------------------------------------------------------------
--  13.37 function Pragmas
------------------------------------------------------------------------------

   function Pragmas
     (The_Element : Asis.Element)
      return        Asis.Pragma_Element_List;

------------------------------------------------------------------------------
--  The_Element - Specifies the element to query
--
--  Returns the list of pragmas, in their order of appearance, that appear
--  directly within the given The_Element.  Returns only those pragmas that are
--  immediate component elements of the given The_Element.  Pragmas embedded
--  within other component elements are not returned.  For example, returns
--  the pragmas in a package specification, in the statement list of a loop,
--  or in a record component list.
--
--  This query returns exactly those pragmas that are returned by the
--  various queries, that accept these same argument kinds, and that
--  return Declaration_List and Statement_List, where the inclusion of
--  Pragmas is controlled by an Include_Pragmas parameter.
--
--  Returns a Nil_Element_List if there are no pragmas.
--
--  Appropriate Element_Kinds:
--        A_Path                          (pragmas from the statement list +
--                                         pragmas immediately preceding the
--                                         reserved word "when" of the first
--                                         alternative)
--        An_Exception_Handler            (pragmas from the statement list +
--                                         pragmas immediately preceding the
--                                         reserved word "when" of the first
--                                         exception handler)
--
--  Appropriate Declaration_Kinds:
--        A_Procedure_Body_Declaration    (pragmas from declarative region +
--                                                      statements)
--        A_Function_Body_Declaration     (pragmas from declarative region +
--                                                      statements)
--        A_Package_Declaration           (pragmas from visible + private
--                                                      declarative regions)
--        A_Package_Body_Declaration      (pragmas from declarative region +
--                                                      statements)
--        A_Task_Body_Declaration         (pragmas from declarative region +
--                                                      statements)
--        A_Protected_Body_Declaration    (pragmas from declarative region)
--        An_Entry_Body_Declaration       (pragmas from declarative region +
--                                                      statements)
--        A_Generic_Procedure_Declaration (pragmas from formal declarative
--                                                      region)
--        A_Generic_Function_Declaration  (pragmas from formal declarative
--                                                      region)
--        A_Generic_Package_Declaration   (pragmas from formal + visible +
--                                           private declarative regions)
--
--  Appropriate Definition_Kinds:
--        A_Record_Definition             (pragmas from the component list)
--        A_Variant_Part                  (pragmas immediately preceding the
--                                         first reserved word "when" + between
--                                         variants)
--        A_Variant                       (pragmas from the component list)
--        A_Task_Definition               (pragmas from visible + private
--                                         declarative regions)
--        A_Protected_Definition          (pragmas from visible + private
--                                         declarative regions)
--
--  Appropriate Statement_Kinds:
--        A_Loop_Statement                (pragmas from statement list)
--        A_While_Loop_Statement          (pragmas from statement list)
--        A_For_Loop_Statement            (pragmas from statement list)
--        A_Block_Statement               (pragmas from declarative region +
--                                                      statements)
--        An_Accept_Statement             (pragmas from statement list +
--
--  Appropriate Representation_Clause_Kinds:
--        A_Record_Representation_Clause  (pragmas from component
--                                                      specifications)
--
--  Returns Element_Kinds:
--       A_Pragma
--
------------------------------------------------------------------------------
--  13.38 function Corresponding_Pragmas
------------------------------------------------------------------------------

   function Corresponding_Pragmas
     (Element : Asis.Element)
      return    Asis.Pragma_Element_List;

------------------------------------------------------------------------------
--  Element - Specifies the element to query
--
--  Returns the list of pragmas semantically associated with the given element,
--  in their order of appearance, or, in any order that does not affect their
--  relative interpretations.  These are pragmas that directly affect the
--  given element.  For example, a pragma Pack affects the type it names.
--
--  Returns a Nil_Element_List if there are no semantically associated pragmas.
--
--  --|D2005 start
--  See the discussion for
--  Asis.Declarations.Corresponding_Representation_Clauses (15.17), we have
--  exactly the same problem for this query.
--  --|D2005 end
--
--  --|AN Application Note:
--  --|AN
--  --|AN If the argument is a inherited entry declaration from a derived task
--  --|AN type, all pragmas returned are elements taken from the original task
--  --|AN type's declarative item list. Their Enclosing_Element is the original
--  --|AN type definition and not the derived type definition.
--  --|AN
--  Appropriate Element_Kinds:
--       A_Declaration
--       A_Statement
--  --|D2005 start
--  How A_Statement can be an appropriate kind for this query???
--  --|D2005 end
--
--  Returns Element_Kinds:
--       A_Pragma
--

------------------------------------------------------------------------------
--  13.39 function Pragma_Name_Image
------------------------------------------------------------------------------

   function Pragma_Name_Image
     (Pragma_Element : Asis.Pragma_Element)
      return           Program_Text;

------------------------------------------------------------------------------
--  Pragma_Element  - Specifies the element to query
--
--  Returns the program text image of the simple name of the pragma.
--
--  The case of names returned by this query may vary between implementors.
--  Implementors are encouraged, but not required, to return names in the
--  same case as was used in the original compilation text.
--
--  Appropriate Element_Kinds:
--       A_Pragma
--
------------------------------------------------------------------------------
--  13.40 function Pragma_Argument_Associations
------------------------------------------------------------------------------

   function Pragma_Argument_Associations
     (Pragma_Element : Asis.Pragma_Element)
      return           Asis.Association_List;

------------------------------------------------------------------------------
--  Pragma_Element - Specifies the element to query
--
--  Returns a list of the Pragma_Argument_Associations of the pragma, in their
--  order of appearance.
--
--  Appropriate Element_Kinds:
--       A_Pragma
--
--  Returns Element_Kinds:
--       A_Pragma_Argument_Association
--
--  --|AN Application Note:
--  --|AN
--  --|AN The SPARK-specific pragma Depends is treated in a special way: it is
--  --|AN always considered that the pragma has a record aggregate as its
--  --|AN (single) argument even if there is no brackets provided as a part
--  --|AN of this aggregate. That is, the following pragmas:
--  --|AN
--  --|AN     pragma Depends ((A => + B));
--  --|AN and
--  --|AN     pragma Depends (A => + B);
--  --|AN
--  --|AN both have a record aggregate '(A => + B)' as their argument. This
--  --|AN does not follow literally the pragma argument syntax defined by the
--  --|AN Ada Standard, but this allows to process all the forms of pragma
--  --|AN Depends in the same way.

------------------------------------------------------------------------------
--  13.41 function Debug_Image
------------------------------------------------------------------------------

   function Debug_Image (Element : Asis.Element) return Wide_String;

------------------------------------------------------------------------------
--  Element - Specifies the program element to convert
--
--  Returns a string value containing implementation-defined debug
--  information associated with the element.
--
--  The return value uses Asis.Text.Delimiter_Image to separate the lines
--  of multi-line results.  The return value does not end with
--  Asis.Text.Delimiter_Image.
--
--  These values are intended for two purposes.  They are suitable for
--  inclusion in problem reports sent to the ASIS implementor.  They can
--  be presumed to contain information useful when debugging the implementation
--  itself. They are also suitable for use by the ASIS application when
--  printing simple application debugging messages during application
--  development.  They are intended to be, to some worthwhile degree,
--  intelligible to the user.
--

------------------------------------------------------------------------------
--  13.42 function Hash
------------------------------------------------------------------------------

   function Hash (Element : Asis.Element) return Asis.ASIS_Integer;

--  The purpose of the hash function is to provide a convenient name for an
--  object of type Asis.Element in order to facilitate application defined I/O
--  and/or other application defined processing.
--
--  The hash function maps Asis.Element objects into N discrete classes
--  ("buckets") of objects.  A good hash function is uniform across its range.
--  It is important to note that the distribution of objects in the
--  application's domain will affect the distribution of the hash function.
--  A good hash measured against one domain will not necessarily be good when
--  fed objects from a different set.
--
--  A continuous uniform hash can be divided by any N and provide a uniform
--  distribution of objects to each of the N discrete classes. A hash value is
--  not unique for each hashed Asis.Element. The application is responsible for
--  handling name collisions of the hashed value.
--
--  The hash function returns a hashed value of type ASIS_Integer. If desired,
--  a user could easily map ASIS_Integer'Range to any smaller range for the
--  hash based on application constraints (i.e., the application implementor
--  can tune the time-space tradeoffs by choosing a small table, implying
--  slower lookups within each "bucket", or a large table, implying faster
--  lookups within each "bucket").

------------------------------------------------------------------------------

------------------------------------------------------------------------------
--  13.???  Corresponding_End_Name
------------------------------------------------------------------------------
   function Corresponding_End_Name
      (Element : Asis.Element)
       return    Asis.Element;
----------------------------------------------------------------------
--  E - Specifies the construct (declaration or statement) to query
--
--  Returns the name after the "end" of the construct
--
--  Returns Nil_Element if there is no such name
--
--  The result can never be Is_Part_Of_Implicit, so queries from Asis.Text
--  (such as Element_Image and Element_Span) can be obtained to it as to any
--  explicit Element. However, the result Element is never visited by
--  instantiations of Traverse_Element.
--
--  The Enclosing_Element of the result Is_Equal to an argument Element.
--
--  If the result is of A_Selected_Component kind, it can be decomposed by
--  structural queries as any other A_Selected_Component Element.
--
--  If the result is of An_Identifier or An_Operator_Symbol kind,
--  Corresponding_Name_Definition, Corresponding_Name_Declaration and
--  Corresponding_Name_Definition_List raise ASIS_Inappropriate_Element when
--  applied to it.
--
--  Expected Declaration_Kinds:
--       A_Package_Declaration
--       A_Package_Body_Declaration
--       A_Procedure_Body_Declaration
--       A_Function_Body_Declaration
--       A_Generic_Package_Declaration
--       A_Task_Type_Declaration
--       A_Single_Task_Declaration
--       A_Task_Body_Declaration
--       A_Protected_Type_Declaration
--       A_Single_Protected_Declaration
--       A_Protected_Body_Declaration
--       An_Entry_Body_Declaration
--
--  Expected Statement_Kinds:
--       A_Loop_Statement
--       A_While_Loop_Statement
--       A_For_Loop_Statement
--       A_Block_Statement
--       An_Accept_Statement
--
--  Returns an element that has one of the following Expression_Kinds:
--       An_Identifier
--       An_Operator_Symbol
--       A_Selected_Component

end Asis.Elements;
