Teaching new tricks to an old dog (C++ -->Ada)

[Turamnvia Suouriviaskimatta]

I 'm following various posting in "comp.lang. ada, comp.lang.c++ ,
comp.realtime, comp.software-eng" groups regarding selection of a
programming language of C, C++ or Ada for safety critical real-time
applications. The majority of expert/people recommend Ada for safety
critical real-time applications. I've many years of experience in C/C++ (and
Delphi) but no Ada knowledge.

May I ask if it is too difficult to move from C/C++ to Ada?
What is the best way of learning Ada for a C/C++ programmer?

[Wouter van Ooijen]

>It's kind of like driving. You can get into a lot of trouble if you do not

follow the traffic laws (you just have to obey the physicla ones ;-), but so
long as you do driving is a fairly safe practice.

Yet modern cars have many 'assist' features that try to prevent
dangerous behaviour of the driver. I know I have to brake
'oscillating' (forgive my language - feel free to try Dutch), but I am
glad my brake system will do it for me in the split second that I see
that car in front of me standing still.
Wouter van Ooijen

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Webshop for PICs and other electronics
http://www.voti.nl/hvu
Teacher electronics and informatics

[Wouter van Ooijen]

>> Although I attempt to drive safely, I also rely on seat belts and air

bags.

I hope we all do. What i meant to say was that using a seat belt isn't an
excuse to drive on the wrong side of the road.

It think what you say translates to 'driving on the right side of the
road is a propper excuse for not using the seat belt'?
Wouter van Ooijen

-- ------------------------------------
http://www.voti.nl
Webshop for PICs and other electronics
http://www.voti.nl/hvu
Teacher electronics and informatics

[Martin Dowie]

Wouter van Ooijen (www.voti.nl) wrote:

Ada can teach C++ how to do templates properly.

I am definitely an Ada fan, but C++ templates are much much more
powerfull. AFAIK C++ is the only language in which you can create a
'unit' based type system that is almost fully compile-time checked.

There is are various ways of doing this in Ada just now but they are not
zero-cost. A new way nearly made it into the Ada2005 standard, but was
going to take too long to 'get right' so it was dropped. Might be looked
at again for the 5-year ISO 'mini' revision. I hope so anyway.

Cheers

-- Martin

[Peter Koch Larsen]

"Wouter van Ooijen (www.voti.nl)" <wo****@voti.nl > skrev i en meddelelse
news:42******** *********@news. xs4all.nl...

My conclusion is that there are some nice ideas out there, but that they
mainly protect against the "sloppy" programmer.

You are absolutely right.

The point that you are probably missing is that *everyone* is a sloppy
programmer every once in a while. The frequency of this sloppiness of
course varies, but it is never zero. So every sloppy mistake caught by
the compiler is a good thing.
Wouter van Ooijen

-- ------------------------------------
http://www.voti.nl
Webshop for PICs and other electronics
http://www.voti.nl/hvu
Teacher electronics and informatics

Which is why other means are needed for quality software. Rigorous testing
and code reviews come to mind.

/Peter

[Wes Groleau]

Frank J. Lhota wrote:

"Ioannis Vranos" <iv*@remove.thi s.grad.com> wrote in message
news:1110055473 .613245@athnrd0 2...

You can also express constraints in templates. An important thing is this.
Are Ada's generics run-time or compile time?

Compile time with every Ada compiler I've used.

What do you both of you mean by compile-time?

Any compliant Ada-83 or Ada-95 compiler can have generics
nested inside of subprograms whose parameters vary according
to run-time parameters or computed values from a higher scope.

--
Wes Groleau

People would have more leisure time if it weren't
for all the leisure-time activities that use it up.
-- Peg Bracken

[Wes Groleau]

Peter Koch Larsen wrote:

I hope we all do. What i meant to say was that using a seat belt isn't an
excuse to drive on the wrong side of the road.

<sarcasm type="parody>

But who the #$%^& would want to live anywhere
where somebody else tells you what side of the
road you HAVE to drive on?

And only an incompetent driver would buy a car
that was unable to drive on the wrong side of the road!

</sarcasm>

--
Wes Groleau
Free Genealogical Lookups:
http://groleau.freeshell.org/ref/lookups.shtml

[jimmaureenrogers]

Peter Koch Larsen wrote:

"Wouter van Ooijen (www.voti.nl)" <wo****@voti.nl > skrev i en meddelelse news:42******** *********@news. xs4all.nl...

My conclusion is that there are some nice ideas out there, but that theymainly protect against the "sloppy" programmer.
You are absolutely right.

The point that you are probably missing is that *everyone* is a sloppy programmer every once in a while. The frequency of this sloppiness of course varies, but it is never zero. So every sloppy mistake caught by the compiler is a good thing.

[snip]
Which is why other means are needed for quality software. Rigorous testing and code reviews come to mind.

Ada does not replace rigorous testing or code reviews. It supplements
them. Code reviews are extremely helpful. They also consume a lot of
time for the development team when they are done well. It is best to
remove as many silly errors from the code through automatic analysis
before exposing the code to developers for review.

I have never worked in an organization where code was judged ready for
review if it had not already produced a clean compile, with no warnings
or errors. When doing C code this meant also passing lint with no
errors or warnings.

The Ada compiler effectively combines the error messages common to a
good C compiler with the error and warning messages common to a good
lint tool. When you get a clean compile from an Ada compiler you are
ready to expose your code to others for a code review.

Jim Rogers

[Wes Groleau]

Martin Krischik wrote:

But as I said, not impossible. I have a regex generic which can be
instanciated for character and wide character strings and basicly any other
descreed type you want to run regular expressing over.

Is that for sale or open-source or not available?

--
Wes Groleau
----
The man who reads nothing at all is better educated
than the man who reads nothing but newspapers.
-- Thomas Jefferson

[Paul E. Bennett]

Peter Koch Larsen wrote:

"Wouter van Ooijen (www.voti.nl)" <wo****@voti.nl > skrev i en meddelelse
news:42******** *********@news. xs4all.nl...

>My conclusion is that there are some nice ideas out there, but that they
mainly protect against the "sloppy" programmer.
You are absolutely right.

The point that you are probably missing is that *everyone* is a sloppy
programmer every once in a while. The frequency of this sloppiness of
course varies, but it is never zero. So every sloppy mistake caught by
the compiler is a good thing.

Even I admit to having my sloppy moments. Fortunately they don't last too
long and reviews and/or testing catch those moments before they progress
very far.
Which is why other means are needed for quality software. Rigorous testing
and code reviews come to mind.

Something that some people here seem not able to accept because they
believe in the absolute protectiveness of their compiler.

--
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Paul E. Bennett ............... .....<email://pe*@amleth.demo n.co.uk>
Forth based HIDECS Consultancy .....<http://www.amleth.demo n.co.uk/>
Mob: [phone]
Tel: [phone]
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[Paul E. Bennett]

ji************* *@worldnet.att. net wrote:

Ada does not replace rigorous testing or code reviews. It supplements
them. Code reviews are extremely helpful. They also consume a lot of
time for the development team when they are done well. It is best to
remove as many silly errors from the code through automatic analysis
before exposing the code to developers for review.
Thanks for that Jim. At least you seem to have been the first (assumed)
Ada user that has admitted that the compiler is not the final arbiter.
I have never worked in an organization where code was judged ready for
review if it had not already produced a clean compile, with no warnings
or errors. When doing C code this meant also passing lint with no
errors or warnings.

The Ada compiler effectively combines the error messages common to a
good C compiler with the error and warning messages common to a good
lint tool. When you get a clean compile from an Ada compiler you are
ready to expose your code to others for a code review.

At least code which passes such a hurdle is in a more reasonable state than
code which has not passed this threshold. I would also hope that you are
not waiting for all the code to pass this hurdle but are compiling,
reviewing and testing on a fairly continuous basis, submitting the code
that passes compile, review and unit testing into the stock for integration
and system testing.

--
*************** *************** *************** *************** ********
Paul E. Bennett ............... .....<email://pe*@amleth.demo n.co.uk>
Forth based HIDECS Consultancy .....<http://www.amleth.demo n.co.uk/>
Mob: [phone]
Tel: [phone]
Going Forth Safely ....EBA. http://www.electric-boat-association.org.uk/
*************** *************** *************** *************** ********