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=-2.9 required=5.0 tests=BAYES_00,FREEMAIL_FROM, MAILING_LIST_MULTI autolearn=unavailable autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,714a8558b02b32bb X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2004-01-22 11:55:35 PST Path: archiver1.google.com!news2.google.com!news.maxwell.syr.edu!newsfeed.icl.net!newsfeed.fjserv.net!proxad.net!usenet-fr.net!enst.fr!melchior!cuivre.fr.eu.org!melchior.frmug.org!not-for-mail From: "amado.alves" Newsgroups: comp.lang.ada Subject: RE: GUI was Re: why Ada is so unpopular ? Date: Thu, 22 Jan 2004 19:03:18 -0000 Organization: Cuivre, Argent, Or Message-ID: NNTP-Posting-Host: lovelace.ada-france.org Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable X-Trace: melchior.cuivre.fr.eu.org 1074798220 62619 80.67.180.195 (22 Jan 2004 19:03:40 GMT) X-Complaints-To: usenet@melchior.cuivre.fr.eu.org NNTP-Posting-Date: Thu, 22 Jan 2004 19:03:40 +0000 (UTC) To: Return-Path: X-MimeOLE: Produced By Microsoft Exchange V6.0.6487.1 content-class: urn:content-classes:message X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: GUI was Re: why Ada is so unpopular ? Thread-Index: AcPhFLewBpV/YhRKRj2vZuMPt+CTpwAASn4O X-OriginalArrivalTime: 22 Jan 2004 19:03:19.0680 (UTC) FILETIME=[66373800:01C3E11A] X-Virus-Scanned: by amavisd-new-20030616-p5 (Debian) at ada-france.org X-BeenThere: comp.lang.ada@ada-france.org X-Mailman-Version: 2.1.3 Precedence: list List-Id: Gateway to the comp.lang.ada Usenet newsgroup List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Xref: archiver1.google.com comp.lang.ada:4674 Date: 2004-01-22T19:03:18+00:00 <<...this doesn't work very well when you drop into a directory with thousands of files. A smart tree widget might just peruse "directory portions", where the tree widget is visible (perhaps a less than trivial exercise). But I suspect they take the easy way out, and require all entries to be loaded in to the widget's dynamic memory...>> A solution to this is to have and use standard iterator signatures, = defined e.g. as formal packages descendants of Ada.Containers. (As an = iterator is clearly an item of container design, iterator signatures = belong there.) Directory_Listing (say) builds an 'internal' iterator, and return an = instantiation of the standard signature, grounded on this internal = iterator. Then all is well. The Directory package would not be using the = Ada.Containers 'engines', but just their specification. (The advantages = include the possiblity of interaction with other standard containers = e.g. perform a deep copy of a part of the tree to send to a GUI object). However, I think Ada.Containers should provide 'real' containers with = the structure and efficiency required by Directories. Even the possible = cyclic graphs of directories with links. If Ada.Containers does not have = this already (I don't recall), it should be a simple (!) matter of = adjusting (basically, generalizing) the structures already in the = reference implementation of Directories (?) and moving them to = Ada.Containers. I suspect these things don't happen because of the communication costs = between the teams working on the several proposals (Containers, = Directories, ASIS, ...) The costs are high, we simply don't have the = means to support them, so there simply is no communication. Result: a = disconnected standard :-(