for S'Image use Func??
in [ADA]
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From: Jeffrey R. Carter on 6 May 2010 18:33 Warren wrote: > > True, but in my case I just needed the leading zeros, sans > any sign: > > 900 to be displayed as "00900" (vs " 900"). In my job we make extensive use of the image functions from PragmARC.Images. These have optional Width, Base, and Zero_Filled parameters. So we'd use function Image is new PragmARC.Images.Signed_Image (Your_Signed_Integer_Type_Here); Image (V, Width => 5, Zero_Filled => True) to get your "00900". (There's also Modular_Image for modular integer types.) We use them a lot just to avoid the leading blank from 'Image, but also for this. The PragmARCs are Ada 95, and many of the packages won't compile with a compiler for the current language, but this one will. http://pragmada.x10hosting.com/ -- Jeff Carter "I soiled my armor, I was so scared." Monty Python & the Holy Grail 71
From: Yannick Duchêne (Hibou57) on 6 May 2010 19:22 Le Fri, 07 May 2010 00:33:00 +0200, Jeffrey R. Carter <spam.jrcarter.not(a)spam.acm.org> a écrit: > The PragmARCs are Ada 95, and many of the packages won't compile with a > compiler for the current language, but this one will. > > http://pragmada.x10hosting.com/ > Although the style is not compatible with mine, so I will not use this for my stuff, I wanted to say these sources are nice reading. Just a question : why the Assert procedure (in PragmARC.Assertion_Handler) ? What was the intent as there is already the Assert pragma ? As far as I know, the Assert pragma was already there with Ada 95. Am I wrong with this point ? -- No-no, this isn't an oops ...or I hope (TM) - Don't blame me... I'm just not lucky
From: Randy Brukardt on 6 May 2010 22:10 "Adam Beneschan" <adam(a)irvine.com> wrote in message news:2318cabb-080c-42a0-8219-21c347abe172(a)o11g2000yqj.googlegroups.com... On May 6, 10:10 am, Warren <ve3...(a)gmail.com> wrote: .... >Broadly, you can't use a FOR attribute specification on every >attribute, just a few select ones that the language specifically says >you can. 'Image isn't one of those. > >I think it's been mentioned a few times on this newsgroup that it >might be nice to have this ability, but I don't see that anyone has >submitted an actual language change proposal. I believe we looked at it semi-seriously back during the Ada 2005, but we ran into some problems (I don't recall the details - might have been visibility) and decided it wasn't worth the headache. It would probably be possible with some work. Randy.
From: Randy Brukardt on 6 May 2010 22:17 "Yannick Duch�ne (Hibou57)" <yannick_duchene(a)yahoo.fr> wrote in message news:op.vca4jlxbxmjfy8(a)garhos... .... >Just a question : why the Assert procedure (in PragmARC.Assertion_Handler) >? What was the intent as there is already the Assert pragma ? As far as I >know, the Assert pragma was already there with Ada 95. Am I wrong with >this point ? A lot of Ada 95 implementations had an Assert pragma, but it was not part of the language until Ada 2005. So if you wanted to be 100% portable, you didn't use it. (I've still never written an Assert pragma.) I actually don't buy the need for the Assert pragma in the first place: such checks are rarely expensive and thus should simply be part of the code always. (And the ones that are expensive need a lot more control than simply on or off: Janus/Ada uses trace switches that can be controlled on a per-unit basis.) But it is so simple that it is harmless even if not very valuable. Thus I didn't oppose adding it to the language. Randy.
From: Randy Brukardt on 6 May 2010 22:20
"Dmitry A. Kazakov" <mailbox(a)dmitry-kazakov.de> wrote in message news:1ojboulapml8w$.1w5gfpk45kh72.dlg(a)40tude.net... > On Thu, 06 May 2010 16:22:03 -0400, Robert A Duff wrote: > >> Warren <ve3wwg(a)gmail.com> writes: >> >>> I agree that it is indeed clumsier. It's just that >>> I tend to use it a lot in debug output, rather than >>> chasing down the package prefix for the To_String() >>> function. I know I can always get away with: >>> >>> Put_Line("The value V=" & T'Image(V)); >> >> I don't understand that. You need to chase down the package >> in which T is declared, which is the same package in which >> To_String (or better, Image) is declared. > > I always declare I/O/formatting stuff in a child package. So, T'Image has > some minor advantages. (The argument would really work if it were V'Image > or V.Image) Except that you can't specify an attribute of a type after it is frozen. So if you could specify T'Image, you couldn't define the Image function that you specified in a child package. Thus Bob is right: the type and the function has to be in the same package. (Well, I guess you could use some other subtype that is declared somewhere else as the prefix. Not sure that helps much.) Randy. |