From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham
	autolearn_force=no version=3.4.4
X-Google-Language: ENGLISH,ASCII-7-bit
X-Google-Thread: 103376,fd63afa4dc364b7e
X-Google-Attributes: gid103376,public
X-Google-ArrivalTime: 2001-03-17 05:14:07 PST
Path: 
 supernews.google.com!sn-xit-03!supernews.com!freenix!fr.usenet-edu.net!usenet-edu.net!fr.clara.net!heighliner.fr.clara.net!grolier!club-internet!not-for-mail
From: Laurent Guerby <guerby@acm.org>
Newsgroups: comp.lang.ada
Subject: Support for per allocation pool selection (was: Better support for
 garbage collection)
Date: 17 Mar 2001 14:14:07 +0100
Organization: Club-Internet (France)
Message-ID: <86itl8v8ps.fsf_-_@acm.org>
References: <98m938$2iod0$1@ID-25716.news.dfncis.de> <861ys03t2f.fsf@acm.org>
 <wccr8zxr77u.fsf@world.std.com> <86bsr15wft.fsf@acm.org>
 <wccg0gdqxui.fsf@world.std.com>
NNTP-Posting-Host: nas20-26.vlt.club-internet.fr
X-Trace: front3m.grolier.fr 984834652 102 195.36.170.26 (17 Mar 2001 13:10:52
 GMT)
NNTP-Posting-Date: 17 Mar 2001 13:10:52 GMT
X-Newsreader: Gnus v5.7/Emacs 20.5
Xref: supernews.google.com comp.lang.ada:5802
Date: 2001-03-17T13:10:52+00:00
List-Id: <comp.lang.ada>

Robert A Duff <bobduff@world.std.com> writes:
> My plan is to have a package that keeps track of the "current pool",
> with a Set_Current_Pool operation, or some such.  And a storage pool
> that redirects Allocate requests to the current pool.  This is somewhat
> error prone.  It is also not task safe, and adding locks would be too
> inefficient (I think).  If Ada had task-local storage, I could make it
> task safe, but still error prone.

Okay I see.

> > You also need a new version of Unchecked_Deallocation with an
> > additional parameter, but no new syntax needed here (and with
> > overloading, no new name).

> U_D is a generic, and is a library unit, and overloading is not
> allowed for generics, nor for lib units.

So new name needed ;-).

Note that close to your Set_Current_Pool idea, we can propose a pragma
to do so:

pragma Use_Pool_Object (T_Ptr, Pool_Object);

then all allocations (via new) of type T_Ptr use the given Pool_Object
in the current scope (and until the next pragma), no new syntax then.

No other people have expressed interest so far. Do you think if I
write down a proposal, it would be considered?

For reference:
> The obvious new T'(Pool_Object, Value) doesn't work unfortunately, so
> may be:
> 
> new T'(Value) at Pool_Object -- may be replace "at" by use/of/with/in???
> 
> [...] I see no way to include the allocation part of this feature without
> new syntax, due to the way 4.8 is written:
> 
>     4.7:
>     qualified_expression ::=
> 	 subtype_mark'(expression) | subtype_mark'aggregate
> 
> If other people have ideas.

-- 
Laurent Guerby <guerby@acm.org>