From: ytomino <aghia05@gmail.com>
Subject: discriminant questions
Date: Sat, 17 Sep 2011 09:30:46 -0700 (PDT)
Date: 2011-09-17T09:30:46-07:00 [thread overview]
Message-ID: <9f37b726-d80b-4d24-bf3f-28a14255f7fd@s20g2000yql.googlegroups.com> (raw)
Hello, I'm excited at the containers of Ada 2012.
I tried to write my code with the style of Ada 2012, and I have some
questions.
1) Why is below code error?
procedure q1 is
generic
type e is private;
package the_package_like_ada2012_vector is
type ref (element : not null access e) is null record;
end the_package_like_ada2012_vector;
generic
type e is private;
type ref (element : not null access e) is private;
package the_package_use_ref is
end the_package_use_ref;
package inst1 is new the_package_like_ada2012_vector (integer);
package inst2 is new the_package_use_ref (integer, inst1.ref); --
error
begin
null;
end q1;
q1.adb:13:65: types of actual discriminants must match formal
q1.adb:13:65: instantiation abandoned
It seems no way to write a generic algorithm independent of a
container.
(without Element or Query_Element of Ada 2005 style)
2) Why non-limited types can not have access discriminant with
default?
procedure q2 is
type t1 (value : integer := 100) is null record; -- ok
type int_access is access all integer;
default : aliased int_access := null;
type t2 (element : access int_access := default'access) is null
record; -- error
begin
null;
end q2;
q2.adb:5:56: (Ada 2005) access discriminants of nonlimited types
q2.adb:5:56: cannot have defaults
I would like to write smart pointer and make that it is able to assign-
able type,
as follows:
declare
a : the_smart_pointer (element => wrap (new Integer'(100)));
b : the_smart_pointer (element => wrap (new Integer'(200)));
begin
a.element.all.all := 300; -- a.all := 300; (if compiler supported
Implicit_Dereference)
b := a; -- it frees element of b on Finalize and add reference
count of a on Assign
end;
Why is it disallowed?
Thank you.
next reply other threads:[~2011-09-17 16:46 UTC|newest]
Thread overview: 89+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-17 16:30 ytomino [this message]
2011-09-17 17:19 ` discriminant questions Dmitry A. Kazakov
2011-09-17 17:46 ` ytomino
2011-09-17 19:41 ` Dmitry A. Kazakov
2011-09-17 22:55 ` ytomino
2011-09-18 8:50 ` Dmitry A. Kazakov
2011-09-18 10:54 ` ytomino
2011-09-18 11:35 ` Dmitry A. Kazakov
2011-09-18 12:41 ` ytomino
2011-09-18 13:17 ` Dmitry A. Kazakov
2011-09-18 16:22 ` ytomino
2011-09-18 16:32 ` ytomino
2011-09-18 18:15 ` Dmitry A. Kazakov
2011-09-18 23:44 ` ytomino
2011-09-19 7:27 ` Dmitry A. Kazakov
2011-09-18 14:43 ` Dmitry A. Kazakov
2011-09-18 16:46 ` Robert A Duff
2011-09-18 18:01 ` Dmitry A. Kazakov
2011-09-18 19:20 ` Maciej Sobczak
2011-09-19 7:39 ` Dmitry A. Kazakov
2011-09-19 20:00 ` Maciej Sobczak
2011-09-20 7:33 ` Dmitry A. Kazakov
2011-09-20 15:45 ` Maciej Sobczak
2011-09-20 16:48 ` Dmitry A. Kazakov
2011-09-20 20:19 ` Maciej Sobczak
2011-09-21 7:48 ` Dmitry A. Kazakov
2011-09-21 20:51 ` Maciej Sobczak
2011-09-22 8:07 ` Dmitry A. Kazakov
2011-09-22 20:57 ` Maciej Sobczak
2011-09-23 7:59 ` Dmitry A. Kazakov
2011-09-23 10:57 ` Georg Bauhaus
2011-09-23 22:30 ` Randy Brukardt
2011-09-23 22:50 ` Randy Brukardt
2011-09-24 6:46 ` Dmitry A. Kazakov
2011-09-26 22:48 ` Randy Brukardt
2011-09-27 8:10 ` Dmitry A. Kazakov
2011-09-27 10:18 ` Georg Bauhaus
2011-09-27 12:14 ` Dmitry A. Kazakov
2011-09-27 15:11 ` Georg Bauhaus
2011-09-27 15:38 ` Dmitry A. Kazakov
2011-09-27 18:06 ` Georg Bauhaus
2011-09-27 19:06 ` Dmitry A. Kazakov
2011-09-29 0:01 ` Georg Bauhaus
2011-09-29 8:26 ` Dmitry A. Kazakov
2011-09-30 1:24 ` Randy Brukardt
2011-09-30 8:10 ` Dmitry A. Kazakov
2011-09-30 10:07 ` Georg Bauhaus
2011-09-30 12:38 ` Dmitry A. Kazakov
2011-09-30 17:40 ` Georg Bauhaus
2011-09-30 18:55 ` Dmitry A. Kazakov
2011-09-23 9:23 ` Stephen Leake
2011-09-23 9:48 ` Dmitry A. Kazakov
2011-09-23 22:42 ` Randy Brukardt
2011-09-24 6:56 ` Dmitry A. Kazakov
2011-09-26 22:43 ` Randy Brukardt
2011-09-24 10:47 ` Stephen Leake
2011-09-24 12:54 ` Simon Wright
2011-09-24 14:46 ` Dmitry A. Kazakov
2011-09-24 16:21 ` Simon Wright
2011-09-24 16:43 ` Dmitry A. Kazakov
2011-09-22 2:52 ` Randy Brukardt
2011-09-22 8:11 ` Dmitry A. Kazakov
2011-09-20 0:01 ` Randy Brukardt
2011-09-20 7:38 ` Dmitry A. Kazakov
2011-09-20 11:11 ` AdaMagica
2011-09-20 12:09 ` Dmitry A. Kazakov
2011-09-20 12:31 ` AdaMagica
2011-09-20 12:57 ` Dmitry A. Kazakov
2011-09-20 23:28 ` ytomino
2011-09-21 5:03 ` AdaMagica
2011-09-21 8:08 ` Dmitry A. Kazakov
2011-09-21 10:03 ` Georg Bauhaus
2011-09-21 10:29 ` Dmitry A. Kazakov
2011-09-22 3:21 ` Randy Brukardt
2011-09-22 3:05 ` Randy Brukardt
2011-09-19 23:35 ` Randy Brukardt
2011-09-20 21:39 ` ytomino
2011-09-22 3:32 ` Randy Brukardt
2011-09-18 16:32 ` ytomino
2011-09-19 14:46 ` ytomino
2011-09-19 15:14 ` Dmitry A. Kazakov
2011-09-19 17:49 ` ytomino
2011-09-20 7:29 ` Georg Bauhaus
2011-09-20 19:50 ` ytomino
2011-09-20 8:08 ` Dmitry A. Kazakov
2011-09-20 18:47 ` ytomino
2011-09-21 8:16 ` Dmitry A. Kazakov
2011-09-21 9:55 ` ytomino
2011-09-22 3:26 ` Randy Brukardt
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