Re: What about Ada?

Re: What about Ada?

[Simon Johnston]

> Hi there,
> I signed onto this list to find out what Ada is about. But so far saw
> only Psacal vs. C vs. Assembler...?
> I use Borland Pascal 7.0 and assembler a lot. But it has limitations.

> -What would be the reasons for me to use Ada?
> -How portable is it?
> -Are there "Integerated Developers enviroments" available?
> -Does it use DOS Seg:Ofs memory scheme's, PMode, 32-bit flat?
> -Can you use it in Windows? For windows?
> -How good is it's database support?
> -Does it allow function and operator overloading?
> -How optimised/fast is the code it produces?
> Someone remarked on the list that Ada does not allow Macro's, but does
> give you the option of using OOP or Procedural. Just like macro's can be
> abused, so can OOP, and I would like to have liked the option of using
> macros. (Pascal does not allow it either:-(

> I know I could have found these answers in books as well, but can you
> imagine investing in something that will not even do what you can do
> already?


with StandardDisclaimer; use StandardDisclaimer;
package Sig is
--,-------------------------------------------------------------------------.
--|Simon K. Johnston - Development Engineer (C++/Ada95) |ICL Retail Systems |
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--|Unix Mail: skj@acm.org                               |Bracknell          |
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end Sig;

What about Ada?

[H Marx]

Hi there,
I signed onto this list to find out what Ada is about. But so far saw
only Psacal vs. C vs. Assembler...?
I use Borland Pascal 7.0 and assembler a lot. But it has limitations.
-What would be the reasons for me to use Ada?
-How portable is it?
-Are there "Integerated Developers enviroments" available?
-Does it use DOS Seg:Ofs memory scheme's, PMode, 32-bit flat?
-Can you use it in Windows? For windows?
-How good is it's database support?
-Does it allow function and operator overloading?
-How optimised/fast is the code it produces?
Someone remarked on the list that Ada does not allow Macro's, but does
give you the option of using OOP or Procedural. Just like macro's can be
abused, so can OOP, and I would like to have liked the option of using
macros. (Pascal does not allow it either:-(

I know I could have found these answers in books as well, but can you
imagine investing in something that will not even do what you can do
already?

Cheers,
Harry Marx.
UNISA
South Africa

Re: What about Ada?

[Aron Felix Gurski]

H Marx wrote:
> 
> Hi there,
> I signed onto this list to find out what Ada is about. But so far saw
> only Psacal vs. C vs. Assembler...?
> I use Borland Pascal 7.0 and assembler a lot. But it has limitations.
> -What would be the reasons for me to use Ada?
> -How portable is it?
> -Are there "Integerated Developers enviroments" available?
> -Does it use DOS Seg:Ofs memory scheme's, PMode, 32-bit flat?
> -Can you use it in Windows? For windows?
> -How good is it's database support?
> -Does it allow function and operator overloading?
> -How optimised/fast is the code it produces?
> Someone remarked on the list that Ada does not allow Macro's, but does
> give you the option of using OOP or Procedural. Just like macro's can be
> abused, so can OOP, and I would like to have liked the option of using
> macros. (Pascal does not allow it either:-(
> 
> I know I could have found these answers in books as well, but can you
> imagine investing in something that will not even do what you can do
> already?
> 
> Cheers,
> Harry Marx.
> UNISA
> South Africa

How about investing a few minutes reading on the web? You can start at

	http://lglwww.epfl.ch/Ada/

Re: What about Ada?

[Carl Bowman]

In article <s2070028.032@alpha.unisa.ac.za>,
H Marx  <MARXH@ALPHA.UNISA.AC.ZA> wrote:
>Hi there,
>I signed onto this list to find out what Ada is about. But so far saw
>only Psacal vs. C vs. Assembler...?
>I use Borland Pascal 7.0 and assembler a lot. But it has limitations.
>-What would be the reasons for me to use Ada?
>-How portable is it?
>-Are there "Integerated Developers enviroments" available?
>-Does it use DOS Seg:Ofs memory scheme's, PMode, 32-bit flat?
>-Can you use it in Windows? For windows?
>-How good is it's database support?
>-Does it allow function and operator overloading?
>-How optimised/fast is the code it produces?
>Someone remarked on the list that Ada does not allow Macro's, but does
>give you the option of using OOP or Procedural. Just like macro's can be
>abused, so can OOP, and I would like to have liked the option of using
>macros. (Pascal does not allow it either:-(
>
>I know I could have found these answers in books as well, but can you
>imagine investing in something that will not even do what you can do
>already?
>
>Cheers,
>Harry Marx.
>UNISA
>South Africa


(This is going to sound like a commercial...get your boots!)


There have been several first-time users posting recently.  I invite
all of these users to visit the Software Engineering host, home of the
Ada Information Clearinghouse (AdaIC) web pages.  The AdaIC supports
the Ada Joint Program Office by gathering and distributing information
for Ada users of all skill levels.


Not only do we have our material online, but links to other excellent
Ada web sites as well.  Those sites are are too numerous to mention
here, but are attributed and listed online.  The Ada community has
placed a lot of useful material at everyone's reach via these
electronic sources.


The URL is http://sw-eng.falls-church.va.us .


Carl Bowman
Ada Information Clearinghouse

Re: What about Ada?

[bourass]

In <s2070028.032@alpha.unisa.ac.za>, H Marx <MARXH@ALPHA.UNISA.AC.ZA> writes:
>Hi there,
>I signed onto this list to find out what Ada is about. But so far saw
>only Psacal vs. C vs. Assembler...?
>I use Borland Pascal 7.0 and assembler a lot. But it has limitations.
>-What would be the reasons for me to use Ada?

Catching bugs at compile-time instead of run-time.  Maintainability.  Very
simple and elegant (therefore useful) multitasking and synchronization.
Language support for large-scale programming.

>-How portable is it?

There are Ada implementations on most major platforms both HW and SW.
It is also standardized, so your source code will not be hard to port.
GUIs of course remain just as problemmatic in Ada as in other languages.

>-Are there "Integerated Developers enviroments" available?

Yes

>-Does it use DOS Seg:Ofs memory scheme's, PMode, 32-bit flat?

Flat memory model, regardless of the platform.

>-Can you use it in Windows? For windows?

Yes

>-How good is it's database support?

Someone else will have to answer.  Ada has the notion of packages -- some of
which have been standardized.  Not being overly involved with database, I
do not know if a standard database package is out there.

>-Does it allow function and operator overloading?

Yes

>-How optimised/fast is the code it produces?

Optimized implementations compete on the same playing field with C.

>Someone remarked on the list that Ada does not allow Macro's, but does
>give you the option of using OOP or Procedural. Just like macro's can be
>abused, so can OOP, and I would like to have liked the option of using
>macros. (Pascal does not allow it either:-(

If you are a die-hard macro fan, just use the macro compiler from your
C tools.  It is not really a compilation step anyway, but a pre-compilation
step.  Anyway, you will quickly find that it is not necessary.  Generic
procedures & packages cover most of the territory usually provided by
macros, if not more...
>
>I know I could have found these answers in books as well, but can you
>imagine investing in something that will not even do what you can do
>already?
>
Forget that idea, Harry.  If you must get your hands on bits and bytes, Ada
does provide the capability you want.  But it also does much more than C,
much more safely.

Regards,

Greg Bourassa

Re: What about Ada?

[David Wheeler]

Simon Johnston (skj@ACM.ORG) wrote:
: > Hi there,
: > I signed onto this list to find out what Ada is about. But so far saw
: > only Psacal vs. C vs. Assembler...?

I suspect others will try to answer your specific questions.
There's a wealth of already-existing material that can try to give you
some answers in terms of "what is Ada"?

To start, use a web browser at look at "Ada Home" at:
   http://lglwww.epfl.ch/Ada/

A painless way to learn how to actually use Ada (which is the best way
to evaluate it for yourself) is to use my "Lovelace" tutorial. Open up:
   http://lglwww.epfl.ch/Ada/Tutorials/Lovelace/lovelace.htm

--- David A. Wheeler
Net address: wheeler@ida.org

Re: What about Ada?

[John Herro]

H Marx <MARXH@ALPHA.UNISA.AC.ZA> asks several
questions about Ada:
>-What would be the reasons for me to use Ada?
     Ada is a lot less error prone than other languages!  Ada catches
errors at compile time that other languages catch only at run time, or not
at all.  Also, Ada programs tend to be easier to read than programs in
other languages, and much easier to modify a month or a year later.
     Here are just two examples out of many:  First, a common error in C
is to dereference a null pointer.  This usually causes a General
Protection Fault on a PC.  In Ada, this same error will stop the program
gracefully and, with most Ada compilers, will report the line number on
which the error occurred (unless you've written an error handler). 
Second, Ada catches out-of-bounds subscripts that C misses.
>-How portable is it?
     Ada programs tend to be much more portable than programs in other
languages.  First, if you have a "validated" Ada compiler, it means that
your compiler conforms exactly to the Ada standard, and doesn't implement
a subset or superset of standard Ada.  (To earn validation, the compiler
must pass an extensive set of tests to be certain that there's no subset
or superset.)
     Also, user defined types in Ada greatly improve portability.  Suppose
you need to count to one million.  In Ada you write
type Counter is range 0 .. 1_000_000;
An Ada compiler that implements type Integer with 32 bits will
automatically select Integer for your type Counter.  If you port your
program to an Ada compiler that implements Integer with 16 bits, the
compiler will automatically select a larger type (e.g., Long_Integer),
without your having to change a line of code!
>-Are there "Integerated Developers enviroments" available?
     Many Ada compilers come with development environments.
>-Does it use DOS Seg:Ofs memory scheme's, PMode, 32-bit flat?
     This depends on the compiler.  I often use Open Ada for DOS, which
comes with Peek and Poke that use Seg:Ofs.
>-Can you use it in Windows? For windows?
     Some Ada compilers, such as Thomsoft's ActivAda and ObjectAda, work
with Windows.  There's a list of Ada compilers available for DOS and
Windows in my Ada Tutor program, which you can download at the Web and FTP
sites below my signature.
>-Does it allow function and operator overloading?
     Yes, and as you probably already know, this improves program
readability.
>-How optimised/fast is the code it produces?
     Very early Ada compilers earned a reputation for producing
inefficient code, but today's compilers are excellent!  Most of them have
several levels of optimization that you can switch on.
>Someone remarked ... that Ada does not allow macros
     This was done for a very good reason: they're too error prone and
hurt program readability.  However, Ada has named numbers and renaming, to
achieve some of the benefits of macros safely.

     You'll like Ada!  Download the Ada Tutor program (which does NOT
require a compiler when run on a PC), and like me, you'll become an
enthusiastic convert!
- John Herro
Software Innovations Technology
http://members.aol.com/AdaTutor
ftp://members.aol.com/AdaTutor

Re: What about Ada?

[Ted Dennison]

H Marx wrote:
> 
> Hi there,
> I signed onto this list to find out what Ada is about. But so far saw
> only Psacal vs. C vs. Assembler...?

People like to post provocative questions here that are crossposted to
naturally antagonistic groups. The replies tend to dominate the traffic
here (out of proportion to most people's interest in them). Welcome to
USENET.

> I use Borland Pascal 7.0 and assembler a lot. But it has limitations.
> -What would be the reasons for me to use Ada?

The best reason over Borland Pascal is support of multi-threaded 
algorithms (tasking).

> -How portable is it?
If you stick to the defined language, quite portable. If you need to use
platform-specific libraries, then obviously that code won't be portable.
(Only very simple I/O is defined in the Ada standard.)

> -Are there "Integerated Developers enviroments" available?
Sure. Ada vendors sort of pioneered this approach, although few have ever
been quite as snazzy as Visual C++.

> -Does it use DOS Seg:Ofs memory scheme's, PMode, 32-bit flat?
It depends on the compiler.

> -Can you use it in Windows? For windows?
There are windows compilers, yes.

> -How good is it's database support?
If you want to make your own simple databases, you can use standard Ada
with no problem. Otherwise, you will have to use some sort of interface
library (just like with any other language).

> -Does it allow function and operator overloading?
Yup. 

> -How optimised/fast is the code it produces?
It depends on the compiler. Some are quite mature (=> good).

> Someone remarked on the list that Ada does not allow Macro's, but does
> give you the option of using OOP or Procedural. Just like macro's can be
> abused, so can OOP, and I would like to have liked the option of using
> macros. (Pascal does not allow it either:-(

Ada programs can (and do) allow the use of generic units (much like C++
templates) to achieve the same effect in a much less error-prone manner.
If you still want macros, there's nothing stopping you from using your
own pre-processor.

-- 
T.E.D.          
                |  Work - mailto:dennison@escmail.orl.mmc.com  |
                |  Home - mailto:dennison@iag.net              |
                |  URL  - http://www.iag.net/~dennison         |

Re: What about Ada?

[Daniel P Hudson]

H Marx <MARXH@ALPHA.UNISA.AC.ZA> wrote:
>Hi there,
>I signed onto this list to find out what Ada is about. But so far saw
>only Psacal vs. C vs. Assembler...?

>I use Borland Pascal 7.0 and assembler a lot. But it has limitations.

 I'm not even going to ask you what limitations you have found in ASM
 because I don't want to know.

>-What would be the reasons for me to use Ada?

 Either someone is paying you to use it or you feel comfortable using it,
 what other reasons are there?

>-How portable is it?

 Hmm, Not sure since they just developed another standard for Ada, whats
 that like 10 now or something?

>-Are there "Integerated Developers enviroments" available?

 But of corse.

>-Does it use DOS Seg:Ofs memory scheme's, PMode, 32-bit flat?

 If it runs in Dos is hardly has a choice, but the GNAT package from
 GNU is a 32Bit system so no it doesn't use Intel's 16Bit hack to
 make use 20Bit address, it just uses a 32Bit pointer which gives you what
 4GB to choose from?

>-Can you use it in Windows? For windows?

 I believe I saw an Ada compiler for Win 3.x in programmer's paradise about
 4 months ago, but don;t quote me on that.

>-How good is it's database support?

 It was originally use by the millitary, I'd say its got a good chance
 of being Database friendly, now DBASE, etc. friendly is another story.

>Someone remarked on the list that Ada does not allow Macro's, but does
>give you the option of using OOP or Procedural. Just like macro's can be
>abused, so can OOP, and I would like to have liked the option of using
>macros. (Pascal does not allow it either:-(

 OK, you want to find out about Ada? Here is a URL actually here is 
 2 URLS that shoudl supply you with ample amounts of data

 ftp://sunsite.doc.ic.ac.uk/packages/simtel/msdos/ada - grab the tutorial
 http://www.afn.org/~afn03257 - follow the 3 language list entries for
                                info on more languages than you can imagine.

Re: What about Ada?

[Robert Dewar]

Daniel said

" Hmm, Not sure since they just developed another standard for Ada, whats
 that like 10 now or something?"

Daniel, I guess you are not very familiar with Ada! There have been
precisely TWO standards for Ada, the original Ada, now referred to as
Ada 83, and the current Ada standard, referred to as Ada 95. These are
the only two standards, they appeared in 1983 and 1995 respectively.
Unlike the situation with Pascal, the ANSI standard is identical to
the ISO standard.

Perhaps you meant 10 in base 2? :-)

In Ada, we spell this as 2#10#

Re: What about Ada?

[Daniel P Hudson]

dewar@cs.nyu.edu (Robert Dewar) wrote:
>Daniel said

>" Hmm, Not sure since they just developed another standard for Ada, whats
> that like 10 now or something?"

>Daniel, I guess you are not very familiar with Ada! There have been
>precisely TWO standards for Ada, the original Ada, now referred to as
>Ada 83, and the current Ada standard, referred to as Ada 95. These are
>the only two standards, they appeared in 1983 and 1995 respectively.
>Unlike the situation with Pascal, the ANSI standard is identical to
>the ISO standard.

>Perhaps you meant 10 in base 2? :-)

 That covers ISO, now try the DoD's standards that came before ANSI/ISO
 stuck their nose in it. Back when ACVC was responcible for determining
 whether or not a implementation was conforming, actually I think they still
 do this today maybe, although I doubt anyone checks to see whether it
 has thier OK or not. There aren't actually 10, maybe 5 or 6 different 
 standards for Ada from its original implementation by the Dod up to
 today's ISO Ada 9X' [95' isn't it?].

Re: What about Ada?

[Robert Dewar]

Daniel said

" That covers ISO, now try the DoD's standards that came before ANSI/ISO
 stuck their nose in it. Back when ACVC was responcible for determining
 whether or not a implementation was conforming, actually I think they still
 do this today maybe, although I doubt anyone checks to see whether it
 has thier OK or not. There aren't actually 10, maybe 5 or 6 different
 standards for Ada from its original implementation by the Dod up to
 today's ISO Ada 9X' [95' isn't it?]."

Well your unawareness of the current state of ACVC testing certainly shows
you are disconnected from recent history, and your claims about DoD's
standards shows you are disconnected from ancient history as well.

It's amazing how rumours like this spread with no basis in fact whatsoever.

The facts (who knows if mere facts are enough to encourage determined
ignorance :-) are that there was a military standard for Ada 83 (Mil Std 1815)
an ANSI standard, and an ISO standard, and they are all ABSOLUTELY IDENTICAL.

The Ada 83 ACVC suites (with which I believe I am as familiar as anyone!)
tested conformance to the earlier standard (doesn't matter which of the
three you are talking about since they are identical).

The Ada 95 ACVC suites (with which I am also quite familiar!) test conformance
to the Ada 95 standard (doesn't matter whether you choose the ISO standard
or the ANSI standard, again they are identical -- except for some very
minor presentation issues -- the ISO standard omits the paragraph numbers).

As I said before, compared to other languages, notably Pascal, where the
ISO and ANSI standards differ substantively, and Fortran, where there are
two co-existing standards, and wide spread use of a third non-standard
form (HPF), and COBOL, where there is widespread use of a non-standard
form (OOCOBOL), and C++ (where there is no standard), the standarization
of Ada is very clean and easy to understand.

P.S. I think there are also notional FIPS standards, probably for both
versions, but these are also identical, and in fact I believe are by
reference standards.

Bottom line, there have been precisely TWO standards for Ada, that's it!

Re: What about Ada?

[Howard W. LUDWIG]

Daniel P Hudson wrote:
> 
> dewar@cs.nyu.edu (Robert Dewar) wrote:
> >Daniel said
> 
> >" Hmm, Not sure since they just developed another standard for Ada, whats
> > that like 10 now or something?"
> 
> >Daniel, I guess you are not very familiar with Ada! There have been
> >precisely TWO standards for Ada, the original Ada, now referred to as
> >Ada 83, and the current Ada standard, referred to as Ada 95. These are
> >the only two standards, they appeared in 1983 and 1995 respectively.
> >Unlike the situation with Pascal, the ANSI standard is identical to
> >the ISO standard.
> 
>  That covers ISO, now try the DoD's standards that came before ANSI/ISO
>  stuck their nose in it. Back when ACVC was responcible for determining
>  whether or not a implementation was conforming, actually I think they still
>  do this today maybe, although I doubt anyone checks to see whether it
>  has thier OK or not. There aren't actually 10, maybe 5 or 6 different
>  standards for Ada from its original implementation by the Dod up to
>  today's ISO Ada 9X' [95' isn't it?].

I believe there are several items being confused here:

First, the Ada language itself has been through three standardized versions:
	MIL-STD-1815, dated 1980-12-10;
	ANSI/MIL-STD-1815A, dated 1983-01-22 (the motivation for the nomenclature
		Ada 83), also known (with identical definition) as ISO 8652:1987 and
		FIPS 119;
	ANSI/ISO/IEC 8652:1995 (the motivation for the nomenclature Ada 95), also known
		(with identical definition) as FIPS 119-1.
Thus, in terms of broader-based standardization (such as ANSI and ISO, not just the USA
Department of Defense), there have been two versions of the language as Robert Dewar
has pointed out.  There was only one MIL-STD version prior to those; it had been
submitted to ANSI for adoption, but, for various reasons, the MIL-STD was updated with
the newer (1983) version adopted by ANSI.  (Note:  the "A" following the "1815" denotes
the first revision of the MIL-STD; with the changes in procurement policy, the DOD will
use the ANSI/ISO standard rather than MIL-STD, so the MIL-STD-1815 will be regarded as
superseded and not revised to follow ANSI/ISO.  This demonstrates that there was only
one pre-ANSI/ISO definition of Ada, namely MIL-STD-1815.)

Third, just to make sure there is no confusion on this point, there was a sequence
of requirements documents (Strawman .. Steelman) to specify what the (at that time)
new language would need to do, but none of them constituted a definition of the
language itself.

Second, in order to carry the Ada certification mark, an Ada compiler must complete
successfully and officially the Ada validation process, meaning to pass the requisite
tests in the Ada Compiler Validation Capability (ACVC) suite.  For Ada 83, the suites
were named 1.n, where n got up to 11.  For Ada 95, they are named 2.n.  Different
suite versions do NOT constitute different definitions of the language.  They simply
correspond to our growth in experience with what sorts of tests need to be run to
provide more confidence in the validation of compilers against the stable standard.

Howard W. LUDWIG

Working, but not speaking, for Lockheed Martin Electronics & Missiles Co.