Are there noticable differences in Ada acceptance by country?

Are there noticable differences in Ada acceptance by country?

[Mike Silva]

Some comments about Ada in the UK made me wonder about this.  Are
there countries where the programming and/or management culture seems
to be more accepting of Ada?  Are there Ada "hotbeds" about in the
world?  And if so, what accounts for the differences?

Mike

Re: Are there noticable differences in Ada acceptance by country?

[Pascal Obry]

Mike Silva a �crit :
> Some comments about Ada in the UK made me wonder about this.  Are
> there countries where the programming and/or management culture seems
> to be more accepting of Ada?  Are there Ada "hotbeds" about in the
> world?  And if so, what accounts for the differences?

My experience is that in France it is not taken seriously in most 
companies outside the avionic domain. For managers Ada is a dead 
language probably because they read in 
"highly-technical-oriented-magazines" that Java this, Java that, Java 
there and Java everywhere ! My experience at least.

Pascal.

-- 

--|------------------------------------------------------
--| Pascal Obry                           Team-Ada Member
--| 45, rue Gabriel Peri - 78114 Magny Les Hameaux FRANCE
--|------------------------------------------------------
--|              http://www.obry.net
--| "The best way to travel is by means of imagination"
--|
--| gpg --keyserver wwwkeys.pgp.net --recv-key C1082595

Re: Are there noticable differences in Ada acceptance by country?

[Phaedrus]

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain, Size: 1894 bytes --]

Pretty much the same story in the USA.  For one thing, the one domain where 
Ada was most-widely used (military) is dominated by companies which 
recognize that contract performance isn't an issue.  "Cost-plus" means never 
having to say that you're done, at least not until the money runs out!

I wonder if we shouldn't take the time to perform a little "Copernican 
inversion".  Instead of asking "Where is Ada used?", how about asking "Where 
would Ada be best used?".  (Saying "everywhere" only muddies the situation, 
so please don't.  No matter how much wishful thinking you employ, it isn't 
true.)  For instance, I've often wondered why Ada isn't used more for 
medical (safety critical) applications.    A toe-hold there would do a lot 
to expand the use of Ada.

Brian

"Pascal Obry" <pascal@obry.net> wrote in message 
news:47E0290D.7080201@obry.net...
> Mike Silva a �crit :
>> Some comments about Ada in the UK made me wonder about this.  Are
>> there countries where the programming and/or management culture seems
>> to be more accepting of Ada?  Are there Ada "hotbeds" about in the
>> world?  And if so, what accounts for the differences?
>
> My experience is that in France it is not taken seriously in most 
> companies outside the avionic domain. For managers Ada is a dead language 
> probably because they read in "highly-technical-oriented-magazines" that 
> Java this, Java that, Java there and Java everywhere ! My experience at 
> least.
>
> Pascal.
>
> -- 
>
> --|------------------------------------------------------
> --| Pascal Obry                           Team-Ada Member
> --| 45, rue Gabriel Peri - 78114 Magny Les Hameaux FRANCE
> --|------------------------------------------------------
> --|              http://www.obry.net
> --| "The best way to travel is by means of imagination"
> --|
> --| gpg --keyserver wwwkeys.pgp.net --recv-key C1082595 

Re: Are there noticable differences in Ada acceptance by country?

[Mike Silva]

On Mar 18, 6:58 pm, "Phaedrus" <phaedrus...@hotmail.com> wrote:
> Pretty much the same story in the USA.  For one thing, the one domain where
> Ada was most-widely used (military) is dominated by companies which
> recognize that contract performance isn't an issue.  "Cost-plus" means never
> having to say that you're done, at least not until the money runs out!
>
> I wonder if we shouldn't take the time to perform a little "Copernican
> inversion".  Instead of asking "Where is Ada used?", how about asking "Where
> would Ada be best used?".  (Saying "everywhere" only muddies the situation,
> so please don't.  No matter how much wishful thinking you employ, it isn't
> true.)  For instance, I've often wondered why Ada isn't used more for
> medical (safety critical) applications.    A toe-hold there would do a lot
> to expand the use of Ada.

Well, if there are identifiable regions where Ada is more accepted, it
might be worthwhile to try and understand why this is the case.  Why
haven't those managers and programmers been as swayed by the C-
descendents wave as in other places?

Re: Are there noticable differences in Ada acceptance by country?

[Ludovic Brenta]

Mike Silva writes:
> Some comments about Ada in the UK made me wonder about this.  Are
> there countries where the programming and/or management culture
> seems to be more accepting of Ada?  Are there Ada "hotbeds" about in
> the world?  And if so, what accounts for the differences?

Ada is like computers; it developed top-down. It was initially
military (like the ENIAC for nuclear weapons research), then spread to
the top end of civil applications (like the first civil mainframes in
the largest banks, or supercomputers in the top research labs), and
then down to more and more mundane applications.  It touched the
bottom when it became possible to write web applications in Ada :)

Not many countries build jet airplanes, satellites, or nuclear power
plants.  These are the countries where you're likely to find the most
Ada software engineers, because that's where Ada came from.

Unfortunately, this elite language for software engineers competes
against lesser languages trying to move up the ladder: C and its
offspring for "hackers", visual or scripting languages for "dummies",
and Lisp and company for "computer scientists".  Why?  Because very
few people want to be software engineers and would rather be hackers,
dummies or computer scientists.  Why?  Because being an elite software
engineer is as difficult as building a deep space probe.

-- 
Ludovic Brenta.

Re: Are there noticable differences in Ada acceptance by country?

[Thomas]

Ludovic Brenta wrote:
> Not many countries build jet airplanes, satellites, or nuclear power
> plants.  These are the countries where you're likely to find the most
> Ada software engineers, because that's where Ada came from.


I personally, from a beginners point of view, find it sad that this very 
competent language seems "stuck" in the world of satellites and nuclear 
power plants.

It should be out there among us "hackers" and "dummies", teaching and 
guiding us into building more solid, secure and maintainable software.

I don't believe the language itself is to blame, as it's not a bit 
harder or more difficult to learn than any other language.

Ada needs LOTS of beginner-friendly tutorials, interesting open source 
projects,  thriving communities and a bunch of people that understands 
that Ada's ability to draw in new users equals its ability to survive. 
If there are no new users coming in (or too few), then Ada usage will 
slowly dwindle and steadily be replaced by Java, C/C++ and, shiver, C#.

Because you CAN build software for nuclear power plants with Java - it 
might not be pretty/easy/maintainable, but if the only programmers you 
can find in the year 2017 are doing Java, then you can be damn well sure 
nuclear power plants will be build using just that.  :)

I'm ranting/rambling now, and I'm completely OT. Sorry about that.

Sincerely,
/Thomas, a happy Ada beginner

Re: Are there noticable differences in Ada acceptance by country?

[Ludovic Brenta]

Thomas wrote:
> Ludovic Brenta wrote:
> > Not many countries build jet airplanes, satellites, or nuclear power
> > plants.  These are the countries where you're likely to find the most
> > Ada software engineers, because that's where Ada came from.
>
> I personally, from a beginners point of view, find it sad that this very
> competent language seems "stuck" in the world of satellites and nuclear
> power plants.

I agree with you and I am trying to do my part to solve this problem,
as a few other people here on comp.lang.ada. I hope more and more
people start spreading the word. Robert Dewar does an excellent job
(he writes a new article in various publications every couple of weeks
or so) but, unfortunately, his position as CEO of AdaCore sometimes
undermines his credibility. Slashdot-type people are all too quick to
dismiss his articles as pure PR, while at the same time buying Sun's
PR about Java. That's why Ada needs grass-roots support from
Enthusiasts.

--
Ludovic Brenta.
Ada - if it's good enough for nuclear submarines, then it's good
enough for me.

Re: Are there noticable differences in Ada acceptance by country?

[framefritti]

Ludovic Brenta ha scritto:

> Thomas wrote:
> > Ludovic Brenta wrote:
> > > Not many countries build jet airplanes, satellites, or nuclear power
> > > plants.  These are the countries where you're likely to find the most
> > > Ada software engineers, because that's where Ada came from.
> >
> > I personally, from a beginners point of view, find it sad that this very
> > competent language seems "stuck" in the world of satellites and nuclear
> > power plants.
>
> I agree with you and I am trying to do my part to solve this problem,

I agree too.  I just returned from a meeting with a student of mine
who is working on
his "final project".  His duty is to develop (in Ada, of course) a
software for P2P live
streaming.  The program has lots of TCP/UDP I/O handled by separate
tasks, protected
objects and so on...  While coming back to my office I tried to
imagine what a mess would
have been writing the software in C...

Re: Are there noticable differences in Ada acceptance by country?

[gpriv]

On Mar 19, 8:51 am, "framefri...@gmail.com" <framefri...@gmail.com>
wrote:
> Ludovic Brenta ha scritto:
>
> > Thomas wrote:
> > > Ludovic Brenta wrote:
> > > > Not many countries build jet airplanes, satellites, or nuclear power
> > > > plants.  These are the countries where you're likely to find the most
> > > > Ada software engineers, because that's where Ada came from.
>
> > > I personally, from a beginners point of view, find it sad that this very
> > > competent language seems "stuck" in the world of satellites and nuclear
> > > power plants.
>
> > I agree with you and I am trying to do my part to solve this problem,
>

> I agree too.  I just returned from a meeting with a student of mine
> who is working on
> his "final project".  His duty is to develop (in Ada, of course) a
> software for P2P live
> streaming.  The program has lots of TCP/UDP I/O handled by separate
> tasks, protected
> objects and so on...  While coming back to my office I tried to
> imagine what a mess would
> have been writing the software in C...

Been there, it is a mess indeed!

George

Re: Are there noticable differences in Ada acceptance by country?

[Ludovic Brenta]

Thomas wrote:
> Ada needs LOTS of beginner-friendly tutorials,

My favourite is John English's "Craft of Object-Oriented Programming":

http://www.cmis.brighton.ac.uk/~je/adacraft/

> interesting open source projects,

Ada is peculiar in that there are few projects but a high proportion
of them are "interesting". There are about a hundred projects on
SourceForge, for example. One has to search for them.

> thriving communities

Maybe I'm overly optimistic, but I think comp.lang.ada is a triving
community.

> and a bunch of people that understands that Ada's ability to draw in new users equals its ability to survive.

This bunch exists, but is not big enough and faces an uphill battle
against inertia and ignorance.

--
Ludovic Brenta.

Re: Are there noticable differences in Ada acceptance by country?

[Tero Koskinen]

On Wed, 19 Mar 2008 05:16:08 -0700 (PDT) Ludovic Brenta wrote:
> Thomas wrote:
> > Ada needs [...]
> > interesting open source projects,
> 
> Ada is peculiar in that there are few projects but a high proportion
> of them are "interesting". There are about a hundred projects on
> SourceForge, for example. One has to search for them.

Although, most of the projects are meant for other Ada developers.
There are very few Ada projects for "normal" users. It would be nice to
see few more open source games or desktop apps written in Ada.

> > thriving communities
> 
> Maybe I'm overly optimistic, but I think comp.lang.ada is a triving
> community.

#Ada IRC-channel at Freenode network is also relatively active.

-- 
Tero Koskinen - http://iki.fi/tero.koskinen/

Re: Are there noticable differences in Ada acceptance by country?

[Jean-Pierre Rosen]

Tero Koskinen a �crit :
> There are very few Ada projects for "normal" users. It would be nice to
> see few more open source games or desktop apps written in Ada.
Like this, for example? http://www.chaumetsoftware.com/en/index.htm

It does not show on the page, but it is fully written in Ada (was 
announced on the french Ada news). Not really open source either, but I 
think it is nice to also see people making money with Ada :-)
-- 
---------------------------------------------------------
            J-P. Rosen (rosen@adalog.fr)
Visit Adalog's web site at http://www.adalog.fr

Re: Are there noticable differences in Ada acceptance by country?

[Tero Koskinen]

On Thu, 20 Mar 2008 09:57:30 +0100 Jean-Pierre Rosen wrote:
> Tero Koskinen a écrit :
> > There are very few Ada projects for "normal" users. It would be nice to
> > see few more open source games or desktop apps written in Ada.
> Like this, for example? http://www.chaumetsoftware.com/en/index.htm

Yes, something like that.

> It does not show on the page, but it is fully written in Ada (was 
> announced on the french Ada news). Not really open source either, but I 
> think it is nice to also see people making money with Ada :-)

My idea of open source Ada projects targeted for end users was that
they could "force" more Ada stuff into distributions and make Ada
more popular in that way. For example, a decent GtkAda application
could attract users who would then demand the application and the GtkAda
library to be bundled with their favourite Linux distribution.

-- 
Tero Koskinen - http://iki.fi/tero.koskinen/

Re: Are there noticable differences in Ada acceptance by country?

[Gautier]

Tero Koskinen:

> My idea of open source Ada projects targeted for end users was that
> they could "force" more Ada stuff into distributions and make Ada
> more popular in that way. For example, a decent GtkAda application
> could attract users who would then demand the application and the GtkAda
> library to be bundled with their favourite Linux distribution.

It is exactly what someone wrote me one week ago when discussing about a Linux, 
and more broadly, a Gtk hull for TeXCAD

   http://sourceforge.net/projects/texcad/

Up to now, there is only a native Windows hull, but the core of that software 
uses only the Ada.* library; this includes a generic display of pictures and the 
capturing of items with a mouse.
If someone is tempted by making a Gtk hull...
______________________________________________________________
Gautier         -- http://www.mysunrise.ch/users/gdm/index.htm
Ada programming -- http://www.mysunrise.ch/users/gdm/gsoft.htm

NB: For a direct answer, e-mail address on the Web site!

Re: Are there noticable differences in Ada acceptance by country?

[svaa]

> I don't believe the language itself is to blame, as it's not a bit
> harder or more difficult to learn than any other language.
>

There are two main reasons to learn a language by your own decision:
a) It's a mainstream language (or at least everybody is talking about
it)
b) it has a special feature (the language itself or the framework)

A common answer to beginners in this group is "Before trying
multitasking you should learn the basis of the language, types, scope,
limited types, etc". It is a wise piece of advise, but it also should
give us a clue of what catches beginners's eyes: Multitasking.

Sometimes I think that a lot of beginners browse the index of any Ada
tutorial like this:
"types..., if..., loops... function... I/O,... packages, ...tasks...
tasks?  protected objects? what's this? wow It is great. Their
concepts are really clear, much clearer than signals up and down,
threads etc. Let's try to do X... let's see what is the syntax of a
'for'."

Ada lacks of a a good IDE (please, don't mention GPS), libraries and
tools. Besides Gnat, any Ada compiler is expensive, really expensive,
including Gnat pro, compiling with gnat is slow (no matter it does
more things that other languages). Most of features are found in other
languages as well more or less. But multitasking... Ada brights on
multitasking.

If you want to advocate Ada, show how wonderful it is for
multitasking, don't talk about long-term maintenance, safety, less
bugs, software engineery or things like that.  Multitasking is the
word.

Unfortunately, there are not  a lot of simple software that needs
multitasking, and not many people has the skills for programing
multitasking. So if no one talks about Ada, there is no compelling
reason for learning it.

Re: Are there noticable differences in Ada acceptance by country?

[Phaedrus]

Good points:

> Ada lacks of a a good IDE (please, don't mention GPS), libraries and
> tools. Besides Gnat, any Ada compiler is expensive, really expensive,
> including Gnat pro <snip>

I've made this point a number of times.  New users don't want open source, 
'cause who wants to develop something that they have to give away?  (Giving 
away the source means giving away the tool, period.)  And they don't want to 
pay much more than they would for a new copy of Visual C++.  Until Gnat Pro 
(The best current compiler, IMHO) or something like it is price competitive 
with VC++ the new users will turn elsewhere.  (Btw, the open source 
confusion around the Gnat derivatives doesn't help make the case for new 
users, either!  Who wants to have to consult a lawyer to pick a compiler?)

> If you want to advocate Ada, show how wonderful it is for
> multitasking, don't talk about long-term maintenance, safety, less
> bugs, software engineery or things like that.  Multitasking is the
> word.

Absolutely RIGHT ON!!!  It's a rare user who cares about the other items. 
But, when you tell them about this fantastic feature that they get BUILT IN, 
you can see their eyes light up!  Let's SELL THE SIZZLE!!!

Bad point:
> <snip> ...compiling with gnat is slow... </snip>

Hmmm, that hasn't been my experience.  In fact, compared to other 
development environments I've been very happy with Gnat.  What is your basis 
of comparison?

Cheers!
Brian


<svaa@ciberpiula.net> wrote in message 
news:aeec2c10-7e9e-4dcd-98e9-f81cb6cc3f78@c19g2000prf.googlegroups.com...
>> I don't believe the language itself is to blame, as it's not a bit
>> harder or more difficult to learn than any other language.
>>
>
> There are two main reasons to learn a language by your own decision:
> a) It's a mainstream language (or at least everybody is talking about
> it)
> b) it has a special feature (the language itself or the framework)
>
> A common answer to beginners in this group is "Before trying
> multitasking you should learn the basis of the language, types, scope,
> limited types, etc". It is a wise piece of advise, but it also should
> give us a clue of what catches beginners's eyes: Multitasking.
>
> Sometimes I think that a lot of beginners browse the index of any Ada
> tutorial like this:
> "types..., if..., loops... function... I/O,... packages, ...tasks...
> tasks?  protected objects? what's this? wow It is great. Their
> concepts are really clear, much clearer than signals up and down,
> threads etc. Let's try to do X... let's see what is the syntax of a
> 'for'."
>
> Ada lacks of a a good IDE (please, don't mention GPS), libraries and
> tools. Besides Gnat, any Ada compiler is expensive, really expensive,
> including Gnat pro, compiling with gnat is slow (no matter it does
> more things that other languages). Most of features are found in other
> languages as well more or less. But multitasking... Ada brights on
> multitasking.
>
> If you want to advocate Ada, show how wonderful it is for
> multitasking, don't talk about long-term maintenance, safety, less
> bugs, software engineery or things like that.  Multitasking is the
> word.
>
> Unfortunately, there are not  a lot of simple software that needs
> multitasking, and not many people has the skills for programing
> multitasking. So if no one talks about Ada, there is no compelling
> reason for learning it. 

Re: Are there noticable differences in Ada acceptance by country?

[gpriv]

On Mar 19, 5:14 pm, "Phaedrus" <phaedrus...@hotmail.com> wrote:
> Good points:
>
> > Ada lacks of a a good IDE (please, don't mention GPS), libraries and
> > tools. Besides Gnat, any Ada compiler is expensive, really expensive,
> > including Gnat pro <snip>
>
> I've made this point a number of times.  New users don't want open source,
> 'cause who wants to develop something that they have to give away?  (Giving
> away the source means giving away the tool, period.)  And they don't want to
> pay much more than they would for a new copy of Visual C++.  Until Gnat Pro
> (The best current compiler, IMHO) or something like it is price competitive
> with VC++ the new users will turn elsewhere.  (Btw, the open source
> confusion around the Gnat derivatives doesn't help make the case for new
> users, either!  Who wants to have to consult a lawyer to pick a compiler?)
>
> > If you want to advocate Ada, show how wonderful it is for
> > multitasking, don't talk about long-term maintenance, safety, less
> > bugs, software engineery or things like that.  Multitasking is the
> > word.
>
> Absolutely RIGHT ON!!!  It's a rare user who cares about the other items.
> But, when you tell them about this fantastic feature that they get BUILT IN,
> you can see their eyes light up!  Let's SELL THE SIZZLE!!!
>

I think strong typing should not be dismissed.  Unfortunately Java-
based (and C/C++/C#) courses don't explain to students that X and Y
coordinates being fundamentally integer (or float) types are not the
same thing. Typing provides a basis for proper reflection of real
world entities and that should be tought at the beginning of every
computer course.

George

> Bad point:
>
> > <snip> ...compiling with gnat is slow... </snip>
>
> Hmmm, that hasn't been my experience.  In fact, compared to other
> development environments I've been very happy with Gnat.  What is your basis
> of comparison?
>
> Cheers!
> Brian
>
> <s...@ciberpiula.net> wrote in message
>
> news:aeec2c10-7e9e-4dcd-98e9-f81cb6cc3f78@c19g2000prf.googlegroups.com...
>
> >> I don't believe the language itself is to blame, as it's not a bit
> >> harder or more difficult to learn than any other language.
>
> > There are two main reasons to learn a language by your own decision:
> > a) It's a mainstream language (or at least everybody is talking about
> > it)
> > b) it has a special feature (the language itself or the framework)
>
> > A common answer to beginners in this group is "Before trying
> > multitasking you should learn the basis of the language, types, scope,
> > limited types, etc". It is a wise piece of advise, but it also should
> > give us a clue of what catches beginners's eyes: Multitasking.
>
> > Sometimes I think that a lot of beginners browse the index of any Ada
> > tutorial like this:
> > "types..., if..., loops... function... I/O,... packages, ...tasks...
> > tasks?  protected objects? what's this? wow It is great. Their
> > concepts are really clear, much clearer than signals up and down,
> > threads etc. Let's try to do X... let's see what is the syntax of a
> > 'for'."
>
> > Ada lacks of a a good IDE (please, don't mention GPS), libraries and
> > tools. Besides Gnat, any Ada compiler is expensive, really expensive,
> > including Gnat pro, compiling with gnat is slow (no matter it does
> > more things that other languages). Most of features are found in other
> > languages as well more or less. But multitasking... Ada brights on
> > multitasking.
>
> > If you want to advocate Ada, show how wonderful it is for
> > multitasking, don't talk about long-term maintenance, safety, less
> > bugs, software engineery or things like that.  Multitasking is the
> > word.
>
> > Unfortunately, there are not  a lot of simple software that needs
> > multitasking, and not many people has the skills for programing
> > multitasking. So if no one talks about Ada, there is no compelling
> > reason for learning it.

Re: Are there noticable differences in Ada acceptance by country?

[Simon Wright]

gpriv@axonx.com writes:

> I think strong typing should not be dismissed.  Unfortunately Java-
> based (and C/C++/C#) courses don't explain to students that X and Y
> coordinates being fundamentally integer (or float) types are not the
> same thing.

I always disliked an X binding which had (sub)types for X, Y
coordinates. Wrong level of abstraction, I thought: use something like

   type Position is record
      X : Float;
      Y : Float;
   end record;

and you get a _lot_ less scope for confusion.

--S

Re: Are there noticable differences in Ada acceptance by country?

[Dmitry A. Kazakov]

On Thu, 20 Mar 2008 20:22:22 +0000, Simon Wright wrote:

> gpriv@axonx.com writes:
> 
>> I think strong typing should not be dismissed.  Unfortunately Java-
>> based (and C/C++/C#) courses don't explain to students that X and Y
>> coordinates being fundamentally integer (or float) types are not the
>> same thing.
> 
> I always disliked an X binding which had (sub)types for X, Y
> coordinates. Wrong level of abstraction, I thought: use something like
> 
>    type Position is record
>       X : Float;
>       Y : Float;
>    end record;
> 
> and you get a _lot_ less scope for confusion.

If no rotations involved I would suggest:

   type Horizontal_Coordinate is new Float;
   type Vertical_Coordinate is new Float;
   type Position is record
       X : Horizontal_Coordinate;
       Y : Vertical_Coordinate;
   end record;

In some cases I would consider making absolute positions and relative
offsets different types, similar to Time and Duration.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de

Re: Are there noticable differences in Ada acceptance by country?

[Simon Wright]

"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:

> On Thu, 20 Mar 2008 20:22:22 +0000, Simon Wright wrote:
>
>> gpriv@axonx.com writes:
>> 
>>> I think strong typing should not be dismissed.  Unfortunately Java-
>>> based (and C/C++/C#) courses don't explain to students that X and Y
>>> coordinates being fundamentally integer (or float) types are not the
>>> same thing.
>> 
>> I always disliked an X binding which had (sub)types for X, Y
>> coordinates. Wrong level of abstraction, I thought: use something like
>> 
>>    type Position is record
>>       X : Float;
>>       Y : Float;
>>    end record;
>> 
>> and you get a _lot_ less scope for confusion.
>
> If no rotations involved I would suggest:
>
>    type Horizontal_Coordinate is new Float;
>    type Vertical_Coordinate is new Float;
>    type Position is record
>        X : Horizontal_Coordinate;
>        Y : Vertical_Coordinate;
>    end record;
>
> In some cases I would consider making absolute positions and relative
> offsets different types, similar to Time and Duration.

Well, to be fair, I suppose I would have used Metres (or Pixels)
rather than plain Float.

  subtype Metres is Float;

But I don't see the real advantage in using different types for H_C
and V_C. How ofen are users actually going to get this wrong? There is
some comment-like advantage to subtyping -- rather like AdaCore's
library packages with eg

  subtype Path_Name is String;

but full typing is only going to clutter the place up with
conversions. Or perhaps you lie to provide all the operations a person
could need (acceleration x duration -> speed etc)?


Why would things be different if there were rotations involved?

Re: Are there noticable differences in Ada acceptance by country?

[gpriv]

On Mar 20, 6:17 pm, Simon Wright <simon.j.wri...@mac.com> wrote:
> "Dmitry A. Kazakov" <mail...@dmitry-kazakov.de> writes:
>
>
>
> > On Thu, 20 Mar 2008 20:22:22 +0000, Simon Wright wrote:
>
> >> gp...@axonx.com writes:
>
> >>> I think strong typing should not be dismissed.  Unfortunately Java-
> >>> based (and C/C++/C#) courses don't explain to students that X and Y
> >>> coordinates being fundamentally integer (or float) types are not the
> >>> same thing.
>
> >> I always disliked an X binding which had (sub)types for X, Y
> >> coordinates. Wrong level of abstraction, I thought: use something like
>
> >>    type Position is record
> >>       X : Float;
> >>       Y : Float;
> >>    end record;
>
> >> and you get a _lot_ less scope for confusion.
>
> > If no rotations involved I would suggest:
>
> >    type Horizontal_Coordinate is new Float;
> >    type Vertical_Coordinate is new Float;
> >    type Position is record
> >        X : Horizontal_Coordinate;
> >        Y : Vertical_Coordinate;
> >    end record;
>
> > In some cases I would consider making absolute positions and relative
> > offsets different types, similar to Time and Duration.
>
> Well, to be fair, I suppose I would have used Metres (or Pixels)
> rather than plain Float.
>
>   subtype Metres is Float;
>
> But I don't see the real advantage in using different types for H_C
> and V_C. How ofen are users actually going to get this wrong?

From my own C experience: using code from different sources X and Y
coordinates in function calls were in different order: foo(x,y);
boo(height, width), etc. Easy to overlook.

George.

> There is
> some comment-like advantage to subtyping -- rather like AdaCore's
> library packages with eg
>
>   subtype Path_Name is String;
>
> but full typing is only going to clutter the place up with
> conversions. Or perhaps you lie to provide all the operations a person
> could need (acceleration x duration -> speed etc)?
>
> Why would things be different if there were rotations involved?

Re: Are there noticable differences in Ada acceptance by country?

[tmoran]

>From my own C experience: using code from different sources X and Y
>coordinates in function calls were in different order: foo(x,y);
>boo(height, width), etc. Easy to overlook.
  Or a bitmap vs a screen position.  A position usually has x,y,
while a pixel is at row,column.  Not to mention bitmaps with y=0 at
the bottom painted on screens with y=0 at the top.  Compared to those,
R.X := Horizontal_Coordinate(Cos(Theta) * Float(P.X) + Sin(Theta) * Float(P.Y));
is downright beautiful.

Re: Are there noticable differences in Ada acceptance by country?

[Jeffrey R. Carter]

gpriv@axonx.com wrote:
> 
> From my own C experience: using code from different sources X and Y
> coordinates in function calls were in different order: foo(x,y);
> boo(height, width), etc. Easy to overlook.

Which is why we don't use C:

Foo (X => X, Y => Y);
Boo (Width => X, Height => Y);

-- 
Jeff Carter
"C++: The power, elegance and simplicity of a hand grenade."
Ole-Hjalmar Kristensen
90

Re: Are there noticable differences in Ada acceptance by country?

[Simon Wright]

"Jeffrey R. Carter" <spam.jrcarter.not@spam.acm.org> writes:

> gpriv@axonx.com wrote:
>>
>> From my own C experience: using code from different sources X and Y
>> coordinates in function calls were in different order: foo(x,y);
>> boo(height, width), etc. Easy to overlook.
>
> Which is why we don't use C:
>
> Foo (X => X, Y => Y);
> Boo (Width => X, Height => Y);

or angles clockwise from North, with X positive East & Y positive North:

  Bearing := Arctan (X => Y, Y => X);

Re: Are there noticable differences in Ada acceptance by country?

[gpriv]

On Mar 21, 12:16 am, "Jeffrey R. Carter"
<spam.jrcarter....@spam.acm.org> wrote:
> gp...@axonx.com wrote:
>
> > From my own C experience: using code from different sources X and Y
> > coordinates in function calls were in different order: foo(x,y);
> > boo(height, width), etc. Easy to overlook.
>
> Which is why we don't use C:

But sometimes we have no choice, unfortunately
:-(

For C++ I come up with macros NEWTYPE(TypName,BaseType) and
SUBTYPE(TypeName,BaseType) that generate structure-envelopes with all
basic arithmetic overloads that somewhat mimics Ada typing
functionality.

NEWTYPE(X_Coord, float);
NEWTYPE(Y_Coord, float);

void Foo(X_Coord x, Y_Coord y);



>
> Foo (X => X, Y => Y);
> Boo (Width => X, Height => Y);
>
> --
> Jeff Carter
> "C++: The power, elegance and simplicity of a hand grenade."
> Ole-Hjalmar Kristensen
> 90

Re: Are there noticable differences in Ada acceptance by country?

[Maciej Sobczak]

On 21 Mar, 20:15, gp...@axonx.com wrote:

> For C++ I come up with macros NEWTYPE(TypName,BaseType) and
> SUBTYPE(TypeName,BaseType) that generate structure-envelopes with all
> basic arithmetic overloads that somewhat mimics Ada typing
> functionality.

Another approach to the same problem:

http://www.msobczak.com/prog/typegen/

--
Maciej Sobczak * www.msobczak.com * www.inspirel.com

Re: Are there noticable differences in Ada acceptance by country?

[Simon Wright]

gpriv@axonx.com writes:

> From my own C experience: using code from different sources X and Y
> coordinates in function calls were in different order: foo(x,y);
> boo(height, width), etc. Easy to overlook.

That was my point (I expect I failed to make it properly): if you use
a record for Coordinate, your chance of getting the components the
wrong way round is hugely reduced, and I don't think the added value
of making the H & V components different _types_ is worth the added
cost.

Re: Are there noticable differences in Ada acceptance by country?

[gpriv]

On Mar 21, 12:39 pm, Simon Wright <simon.j.wri...@mac.com> wrote:
> gp...@axonx.com writes:
> > From my own C experience: using code from different sources X and Y
> > coordinates in function calls were in different order: foo(x,y);
> > boo(height, width), etc. Easy to overlook.
>
> That was my point (I expect I failed to make it properly): if you use
> a record for Coordinate, your chance of getting the components the
> wrong way round is hugely reduced, and I don't think the added value
> of making the H & V components different _types_ is worth the added
> cost.

Is there any runtime cost of using new type if no range is defined?  I
thought that

type X_T is new float;

should be equivalent to float and have effect only at compile time.

George.

Re: Are there noticable differences in Ada acceptance by country?

[Adam Beneschan]

On Mar 21, 12:21 pm, gp...@axonx.com wrote:
> On Mar 21, 12:39 pm, Simon Wright <simon.j.wri...@mac.com> wrote:
>
> > gp...@axonx.com writes:
> > > From my own C experience: using code from different sources X and Y
> > > coordinates in function calls were in different order: foo(x,y);
> > > boo(height, width), etc. Easy to overlook.
>
> > That was my point (I expect I failed to make it properly): if you use
> > a record for Coordinate, your chance of getting the components the
> > wrong way round is hugely reduced, and I don't think the added value
> > of making the H & V components different _types_ is worth the added
> > cost.
>
> Is there any runtime cost of using new type if no range is defined?

Very unlikely, I think.  I think the type of "cost" Simon was talking
about was the added burden (on both writer and reader) of additional
type conversions cluttering up the code, when (in this case) they
probably accomplish very little in the way of preventing programmer
errors.

                                -- Adam

Re: Are there noticable differences in Ada acceptance by country?

[Simon Wright]

Adam Beneschan <adam@irvine.com> writes:

> On Mar 21, 12:21 pm, gp...@axonx.com wrote:
>> On Mar 21, 12:39 pm, Simon Wright <simon.j.wri...@mac.com> wrote:
>>
>> > gp...@axonx.com writes:
>> > > From my own C experience: using code from different sources X and Y
>> > > coordinates in function calls were in different order: foo(x,y);
>> > > boo(height, width), etc. Easy to overlook.
>>
>> > That was my point (I expect I failed to make it properly): if you use
>> > a record for Coordinate, your chance of getting the components the
>> > wrong way round is hugely reduced, and I don't think the added value
>> > of making the H & V components different _types_ is worth the added
>> > cost.
>>
>> Is there any runtime cost of using new type if no range is defined?
>
> Very unlikely, I think.  I think the type of "cost" Simon was talking
> about was the added burden (on both writer and reader) of additional
> type conversions cluttering up the code, when (in this case) they
> probably accomplish very little in the way of preventing programmer
> errors.

That was it, precisely: thanks, Adam!

Re: Are there noticable differences in Ada acceptance by country?

[gpriv]

On Mar 22, 3:02 am, Simon Wright <simon.j.wri...@mac.com> wrote:
> Adam Beneschan <a...@irvine.com> writes:
> > On Mar 21, 12:21 pm, gp...@axonx.com wrote:
> >> On Mar 21, 12:39 pm, Simon Wright <simon.j.wri...@mac.com> wrote:
>
> >> > gp...@axonx.com writes:
> >> > > From my own C experience: using code from different sources X and Y
> >> > > coordinates in function calls were in different order: foo(x,y);
> >> > > boo(height, width), etc. Easy to overlook.
>
> >> > That was my point (I expect I failed to make it properly): if you use
> >> > a record for Coordinate, your chance of getting the components the
> >> > wrong way round is hugely reduced, and I don't think the added value
> >> > of making the H & V components different _types_ is worth the added
> >> > cost.
>
> >> Is there any runtime cost of using new type if no range is defined?
>
> > Very unlikely, I think.  I think the type of "cost" Simon was talking
> > about was the added burden (on both writer and reader) of additional
> > type conversions cluttering up the code, when (in this case) they
> > probably accomplish very little in the way of preventing programmer
> > errors.
>
> That was it, precisely: thanks, Adam!

Sorry for misunderstanding. My initial post had to do with 2-d pixel-
coordinate related issues.  These were integers there and no
transforms used.  For true N-d geometry it's certainly is "cleaner"
design to use vectors and matrices preferably hiding implementation
details.

G.

Re: Are there noticable differences in Ada acceptance by country?

[Dmitry A. Kazakov]

On Thu, 20 Mar 2008 22:17:18 +0000, Simon Wright wrote:

> "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:
> 
>> On Thu, 20 Mar 2008 20:22:22 +0000, Simon Wright wrote:
>>
>>> gpriv@axonx.com writes:
>>> 
>>>> I think strong typing should not be dismissed.  Unfortunately Java-
>>>> based (and C/C++/C#) courses don't explain to students that X and Y
>>>> coordinates being fundamentally integer (or float) types are not the
>>>> same thing.
>>> 
>>> I always disliked an X binding which had (sub)types for X, Y
>>> coordinates. Wrong level of abstraction, I thought: use something like
>>> 
>>>    type Position is record
>>>       X : Float;
>>>       Y : Float;
>>>    end record;
>>> 
>>> and you get a _lot_ less scope for confusion.
>>
>> If no rotations involved I would suggest:
>>
>>    type Horizontal_Coordinate is new Float;
>>    type Vertical_Coordinate is new Float;
>>    type Position is record
>>        X : Horizontal_Coordinate;
>>        Y : Vertical_Coordinate;
>>    end record;
>>
>> In some cases I would consider making absolute positions and relative
>> offsets different types, similar to Time and Duration.
> 
> Well, to be fair, I suppose I would have used Metres (or Pixels)
> rather than plain Float.
> 
>   subtype Metres is Float;

I would probably use fixed point for that.
 
> But I don't see the real advantage in using different types for H_C
> and V_C. How ofen are users actually going to get this wrong?

Quite often in GUI applications.

> There is
> some comment-like advantage to subtyping -- rather like AdaCore's
> library packages with eg
> 
>   subtype Path_Name is String;

Interesting, actually in my libraries, I indeed use Item_Path and Item_Name 
both different new types from String. That helped not to mix paths and
names in the subprograms like Get_Directory, Get_Name, compose path from
parent's path and name etc. I had some nasty bugs using Ada.Directories,
which treats path and names subtypes, therefore I decided to make them
separate types.

> but full typing is only going to clutter the place up with
> conversions. Or perhaps you lie to provide all the operations a person
> could need (acceleration x duration -> speed etc)?

Maybe. But these are different cases to me. I think it is true that 
dimensional algebra should be better built on subtypes. But dimensioned 
values are often applied to some reference points. Like distances measured 
from different places. These cannot be mixed even if they have same 
dimensions. So "meter" is more like "float." You could possibly wish to 
have

   type Distance_From_My_Office is new Meter;

(Actually it should produce a whole new dimensional algebra of types.)

> Why would things be different if there were rotations involved?

Because with rotations coordinates become linear combinations with 
dimensionless coefficients. (The rotation matrix is a matrix exponent so 
that cannot be made dimensioned.)

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de

Subtypes to represent coordinate charts

[Eric Hughes]

On Thu, 20 Mar 2008 22:17:18 +0000, Simon Wright wrote:
> Why would things be different if there were rotations involved?

On Mar 21, 1:52 am, "Dmitry A. Kazakov" <mail...@dmitry-kazakov.de>
wrote:
> Because with rotations coordinates become linear combinations with
> dimensionless coefficients. (The rotation matrix is a matrix exponent so
> that cannot be made dimensioned.)

The coordinates of the transformation matrix are indeed dimensionless
(on balance, see below), but the coordinates of the vectors themselves
can well be dimensioned.  Doing it this way can require type
conversions, but not always, depending on what operation the
application of a rotation matrix represents.  The two prototypical
meanings of the mathematical expression are these: (1) dynamic motion
of a vector within a single coordinate frame and (2) coordinate
conversion of a vector between two overlapping coordinate charts (as
with the definition of a manifold, among others).  In the first
application, there's no coordinate conversion.  In the second, there
is.  The underlying mathematical computations are identical, yet
significantly for a software implementation, the types of these
operations are different.

When dealing with multiple coordinate charts, the good reason to
require chart-specific types is that coordinates change their meaning
when transported from one coordinate frame to another.  For example,
if a coordinate pair represents a point, and the pair (1,1) represents
point P in frame A, then (1,1) won't represent point P in frame B
(except degenerately).  So if you have a type Point, the right sort of
declaration looks like this:
    type Point_in_A is new Point ;
    type Point_in_B is new Point ;
    package Convert_from_A_to_B is new Frame_Conversion( Domain =>
Point_in_A, Range => Point_in_B ) ;
The package Frame_Conversion would contain all the necessary type
conversions.  Presumably it's an entirely pragma(Inline) library.

Having said all this, a transformation matrix that converts between
coordinate frames as above has units (meters in B)/(meters in A).  On
balance, this is dimensionless, but there are context-specific units
hiding behind the scenes.  Thus even declaring such a matrix should
have a declaration that captures these types.  The package
Frame_Conversion is a natural source for such types toward this
purpose.

Eric

Re: Are there noticable differences in Ada acceptance by country?

[Simon Wright]

Simon Wright <simon.j.wright@mac.com> writes:

> but full typing is only going to clutter the place up with
> conversions. Or perhaps you lie to provide all the operations a
                              ^^^ like
> person could need (acceleration x duration -> speed etc)?

Sorry, no insult intended

Re: Are there noticable differences in Ada acceptance by country?

[gpriv]

On Mar 20, 4:22 pm, Simon Wright <simon.j.wri...@mac.com> wrote:
> gp...@axonx.com writes:
> > I think strong typing should not be dismissed.  Unfortunately Java-
> > based (and C/C++/C#) courses don't explain to students that X and Y
> > coordinates being fundamentally integer (or float) types are not the
> > same thing.
>
> I always disliked an X binding which had (sub)types for X, Y
> coordinates. Wrong level of abstraction, I thought: use something like
>
>    type Position is record
>       X : Float;
>       Y : Float;
>    end record;
>
> and you get a _lot_ less scope for confusion.
>
> --S

Well, it won't prevent someone to do:

P1.X := P2.Y;

To make may point clear, let's say:

    type Temperature_Type is new Float;

is not the same entity as

    type Speed_Type is new Float;

and I find it useful to be able to express that in the programming
language.


George.

Re: Are there noticable differences in Ada acceptance by country?

[Ivan Levashew]

svaa@ciberpiula.net пишет:
> If you want to advocate Ada, show how wonderful it is for
> multitasking, don't talk about long-term maintenance, safety, less
> bugs, software engineery or things like that.  Multitasking is the
> word.
There are another kind of users that Ada could be better "sold" to: 
Pascalists.

http://homepage.sunrise.ch/mysunrise/gdm/pascada.htm is too outdated.
UCSD? ISO Pascal? Apple Pascal??? -- Let's give up, guys, Ada seems to 
be stuck in early 90s.


-- 
If you want to get to the top, you have to start at the bottom

Re: Are there noticable differences in Ada acceptance by country?

[Thomas]

Mike Silva wrote:
> Some comments about Ada in the UK made me wonder about this.  Are
> there countries where the programming and/or management culture seems
> to be more accepting of Ada?  Are there Ada "hotbeds" about in the
> world?  And if so, what accounts for the differences?

A friend of mine from USA emailed me this the other day:

 > I talked to a couple of local programmer types and got, "Ada? Didn't
 > Microsoft sell that to IBM back in the '70s?"

So it's probably safe to say that there's no Ada hotbed in his area.  :D

/Thomas

Re: Are there noticable differences in Ada acceptance by country?

[Peter C. Chapin]

Thomas wrote:

>  > I talked to a couple of local programmer types and got, "Ada? Didn't
>  > Microsoft sell that to IBM back in the '70s?"
> 
> So it's probably safe to say that there's no Ada hotbed in his area.  :D

One of my students recently went on a job interview. She put Ada on her 
resume since she is currently taking an Ada course with me. The 
interviewer looked over the list of languages she mentioned: "C... good, 
C++... very good, Ada... What is Ada?" My student said that Ada is an 
object oriented programming language. The interviewer replied, "You mean 
like Ruby?"

I respect Ruby but the comparison of Ruby to Ada made me laugh.

Peter

Re: Are there noticable differences in Ada acceptance by country?

[Phaedrus]

A headhunting shop once called and asked if I knew anything about 80-a, or 
at least that's what I heard.  Took me quite a while to determine that they 
were spelling it!

Seriously, the best advice that I'd give a young programmer is to pick a 
language with a distinctive name.  Trying to search Google or job sites for 
Ada is only slightly easier than searching for C.  Weeding out references to 
the American Dental Association, the Americans with Disabilities Act, or 
A(nother) D(amn) A(cronym) is a real pain in the hindquarters.  (Finally, a 
reason to envy Fortran or Cobol coders!)

We should have named her "Lovelace".  At least then the other hits would be 
interesting!

Cheers!
Brian

"Peter C. Chapin" <pchapin@sover.net> wrote in message 
news:47e0ec63$0$11054$4d3efbfe@news.sover.net...
> Thomas wrote:
>
>>  > I talked to a couple of local programmer types and got, "Ada? Didn't
>>  > Microsoft sell that to IBM back in the '70s?"
>>
>> So it's probably safe to say that there's no Ada hotbed in his area.  :D
>
> One of my students recently went on a job interview. She put Ada on her 
> resume since she is currently taking an Ada course with me. The 
> interviewer looked over the list of languages she mentioned: "C... good, 
> C++... very good, Ada... What is Ada?" My student said that Ada is an 
> object oriented programming language. The interviewer replied, "You mean 
> like Ruby?"
>
> I respect Ruby but the comparison of Ruby to Ada made me laugh.
>
> Peter 

Re: Are there noticable differences in Ada acceptance by country?

[David Thompson]

On Wed, 19 Mar 2008 23:08:06 -0700, Dennis Lee Bieber
<wlfraed@ix.netcom.com> wrote:

> On Wed, 19 Mar 2008 13:21:21 -0800, "Phaedrus" <phaedrusalt@hotmail.com>
> declaimed the following in comp.lang.ada:
> 
> > 
> > We should have named her "Lovelace".  At least then the other hits would be 
> > interesting!
> >
> 	Like... if any one remembers the series... Miguelito Lovelace?
> (repeat villain of "The Wild Wild West")

Sorry, he was (named!) Loveless. Totally different vibe.

Nit: he was always called 'doctor', but I don't recall if he was ever
actually established as degreed or if this was just a title he claimed
for himself -- he was, after all, a megalomaniac crook.

But still more usable than Steve McGarrett's (serious*) archfoe on
Hawaii Five-O: Wo Fat. I don't see any good jokes or puns in 'Wo Fat'.
(* as opposed to lighthearted/comedic archfoe = Avery Filer.)

- formerly david.thompson1 || achar(64) || worldnet.att.net

Re: Are there noticable differences in Ada acceptance by country?

[DScott]

David Thompson wrote:
...
> But still more usable than Steve McGarrett's (serious*) archfoe on
> Hawaii Five-O: Wo Fat. I don't see any good jokes or puns in 'Wo Fat'.
Well, around here most of the diet foods are wo fat according to the two year old.
-- 
Fui et vidi experiri.
=DSM=