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=unavailable autolearn_force=no version=3.4.4 Path: eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!feeder.eternal-september.org!aioe.org!.POSTED!not-for-mail From: "J-P. Rosen" Newsgroups: comp.lang.ada Subject: Re: [Newbie] doubly constrained array, dumb question Date: Mon, 26 Feb 2018 18:02:39 +0100 Organization: Adalog Message-ID: References: <62f83fe5-15d6-41cf-952f-bc3cb077d42f@googlegroups.com> NNTP-Posting-Host: TKk5kT01+2w6guVcOjcsiQ.user.gioia.aioe.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Complaints-To: abuse@aioe.org User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 X-Notice: Filtered by postfilter v. 0.8.3 Content-Language: fr Xref: reader02.eternal-september.org comp.lang.ada:50660 Date: 2018-02-26T18:02:39+01:00 List-Id: Le 26/02/2018 à 17:26, Mehdi Saada a écrit : > Hello. > > I would like an constrained String subtype with narrower bounds that Positive'Range. > How can I do something like: > subtype Possible_Length is NATURAL range 1..80; > subtype T_Line is String (Possible_Length range <>); > ? I know "range <>" isn't included in the definition of "range_constraint". How can I express the same thing. > So that I can get after, a dynamic string with: > A: access T_LINE := new T_LINE'("BLABLABLA"); while checking for its range. > You can't do that, because a subtype can't be both constrained and unconstrainde at the same time... OTOH, you can define your own string type: type Short_String is array (Possible_length range <>) of character; Note that this type will still enjoy string literals, and can be converted back and forth to String. -- J-P. Rosen Adalog 2 rue du Docteur Lombard, 92441 Issy-les-Moulineaux CEDEX Tel: +33 1 45 29 21 52, Fax: +33 1 45 29 25 00 http://www.adalog.fr