Re: Need some light on using Ada or not

[Adrian Hoe <abyhoe@gmail.com>]

On Feb 20, 8:13 am, "Luis P. Mendes" <luislupe...@gmailXXX.com> wrote:
> Fri, 18 Feb 2011 16:20:55 -0800, Edward Fish escreveu:
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> > On Feb 18, 2:52 pm, "Luis P. Mendes" <luislupe...@gmailXXX.com> wrote:
> >> Hi,
>
> >> I have two projects to work, one of them in the data mining field and
> >> another regarding xml parsing.
> >> I've been learning C++ (from a Python, Pascal, VB background), due to
> >> it being fast (sure it depends on the implementation) and because it
> >> has a lot of libraries.
>
> >> But I find C++ a very complex language and Ada appeals to me specially
> >> for its overall safety.  Or maybe also because I don't like to go with
> >> majorities... :-)
>
> >> I have some questions, however, that I'd like to be answered: 1. If Ada
> >> is more type safe and restricted than C++, how can it be significantly
> >> slower?
> >> Please see:http://shootout.alioth.debian.org/u64q/benchmark.php?
> >> test=all&lang=gnat
> >> where for some tests, Ada is 2x, 3x, 4x and 5x slower. For the data
> >> mining field as I want to implement, speed is essential. I'll code in
> >> Linux and use gcc as a compiler/linker.
>
> >> 2. In C++ I can use lots of libraries. I'm thinking on data
> >> visualization libraries, for
> >> examplehttp://www.graphviz.org/Gallery/undirected/softmaint.html.
> >> I've read that Ada can use some C bindings.  Can I use any C library?
> >> Some? Is it easy?
> >> I don't want to drop C++ for Ada to build a project that later has to
> >> be rewritten in C++ because of lack of libraries.
>
> >> 3. Is there any kind of fast xml stream parser library? No DOM or SAX,
> >> just to read attributes.
>
> >> Luis
>
> > I'm going to answer in reverse-order. #3 - There is XMLAda; I mention it
> > only because I've heard of it. I haven't had a need for XML, much less a
> > FAST XML parser. But consider that you might not NEED a full-blown XML
> > parser if what you're doing is relatively simple: you could instead have
> > your type override the 'Read & 'Write attributes in the proper XML
> > format and use Streams.
>
> > #2 - This is highly dependent on you. Some people are perfectly happy
> > with a light binding, in which case it's EASY; some people want a THICK
> > binding in which case it's a bit harder because you have to design an
> > interface which essentially a) hides the C/C++ imports & calls, and b)
> > is in the "Ada Style." To take OpenGL for example instead of a function
> > taking a glenum you would subtype it out so that it takes ONLY the valid
> > values.
>
> > #1 - Speed is HEAVILY dependent on the implementation. Consider, for a
> > moment, sorting. A bubble-sort and a quick-sort are exactly the same in
> > terms of Input/Output [on an array of discrete types], but the speeds
> > are radically different. As Georg mentioned that shootout program used
> > the Unbounded version of strings, and that makes manipulation thereof
> > rather slow... it could likely have been done with normal strings a bit
> > faster but with a bit more effort and "dancing around" the fixed nature
> > of string-lengths.
>
> I'd like to thank everyone that answered.
> For me, that have learnt (or trying to learn) some programming languages
> by myself, with no graduation in this area, C++ really sound cryptic.
> I always like to learn by example, and although Ada must be very well
> documented, it can be not obvious for me to solve some issues.
>
> My main doubt is the amount of aid I can get if I embark in the Ada ship.
> But I surely will give it a try.
> I've read a lot about the language and seen some books.
> Is it or is it not advisable for beginner like me to lear Ada from a 95
> book? I was thinking in the Ada 95: The Craft of Object-Oriented
> Programming book.
> Any other recommended book? The Programming in Ada 2005 seems expensive
> just to try the language.
>
> Free resources from the Internet don't seem to include much howtos or
> guides of the 2005 specification.
> Or did I miss something?
>
> Luis


I have been developing database applications using Ada and as well as
web applications with AWS for some time now. I would say (with my
experience), Ada is a good choice. I can't imagine it if I develop
those monster program in anything else all by myself.

I develop and deploy on Mac OS X.

Get the John Barnes' book. It is sort like a bible of Ada.
--
Adrian Hoe
http://adrianhoe.com