The Return of Ada

Pickens writes "Today when most people refer to Ada it's usually as a cautionary tale. The Defense Department commissioned the programming language in the late 1970s but few programmers used Ada, claiming it was difficult to use. Nonetheless many observers believe the basics of Ada are in place for wider use. Ada's stringency causes more work for programmers, but it will also make the code more secure, Ada enthusiasts say. Last fall, contractor Lockheed Martin delivered an update to ERAM, the Federal Aviation Administration's next-generation flight data air traffic control system — ahead of schedule and under budget, which is something you don't often hear about in government circles. Jeff O'Leary, an FAA software development and acquisition manager who oversaw ERAM, attributed at least part of it to the use of the Ada, used for about half the code in the system."

Comments

we need it where it matters

[r00t]

All that vulnerable client-side code (image libraries, HTML parser, etc.) would be immune to buffer overflows if it were in Ada.

Even better, write it in proof-carrying Ada. (while an aritrary theorem prover is impossible, one can get a theorem prover to work in practice via minor tweaks to the input)

Anything that forces discipline is good.

[ErichTheRed]

I don't think I'm the only one who has had to work with really lousy programming and IT coworkers. One of the good things about the past was that programmers had a much harder time hiding their mistakes. In the days of dual-core processors and tons of RAM, even a mediocre programmer can get Java or any of the .NET languages to produce code that works. Of course, readability, maintainability and speed aren't really a factor.

Is going back to Ada and other similar languages a good idea? Maybe. But I think you could get the same result by just demanding better quality work out of existing languages. People have correctly pointed out that the languages aren't really to blame, because you can write garbage in just about any language.

I sound like an old fogey, but I'd much rather see a smaller IT workforce with a very high skill set than a huge sea of mediocre IT folks. This would help combat outsourcing and the other problems affecting our jobs. Almost everyone I've heard complaining the loudest about outsourcing has been either downright lazy or just not very good at what they do.

I'm primarily a systems engineer/administrator. There are many parallels in my branch of IT to the development branch. We've got the guys who can really pick a system apart and get into the guts of a problem to find the right answer. We also have the ones who search Google for an answer, find one that solves half the problem, and wonder why the system breaks a different way after they deploy it.

Not sure how to solve it, but I think it's a problem that we should work on.

I'm quite fond of Ada

[Alistair Hutton]

I'm actually quite fond of Ada as a language. Yes, it's a very verbose language but unlike, say Java or C#, the verbosity gives you a lot of stuff. It gives you good threading. It gives you a very good encapsulation. It gives you a very nice parameter system for procedures/functions That's a point, it seperates between procedures and functions. It gives very, very, very good typing. Very good typing. It's very good. I like it. It's what I want when I'm doing strong, static typing rather than the wishy-washy getting in the way mess that many other main-stream languages. When I use a type I want it to mean something. It's a good language to teach students about programming in my opinion.

shhh! don't go blabbing this all over the place

[museumpeace]

I make a nice living rewriting Ada systems into C++. When DoD suspended the "only quote us system development costs based on Ada" requirement, most bidders dropped Ada like a burning bag of poop. Its best advances such as exception handling have been picked up by modern system programming languages and even Java. The doctrinaire variable type enforcements have yet to be equaled but OO it really aint. Bottom line, plenty of old defense software systems have few living authors who will admit to knowing the code and upkeep is expensive, talent hard to find. This is ironic since DoD spec'd Ada in the first place because it had a maintenance nightmare of hundreds of deployed languages. So of course the managers think a more popular language with "all the features" of Ada should be a porting target. Eventually even customers demanded modernization and compatibility ports.

I know a few die hard Ada programmers who just love it...but very few. The brilliance of the language can be debated but its moot: no talent pool to speak of.

And besides, Ada is really French. [why did GNU make an ada compiler??????????????]

technology market: you can't separate technical merits from market forces
open source: your market has a small leak and is slowly collapsing.

Re:It is not just the language

[dprovine]

I think that any strongly typed language with lots of compile time and link time checks would be about as good (e.g., Java).

In Ada, you can declare a variable to be an integer in the range 1..100, and if it goes outside that range at any point during its lifetime, an exception is immediately thrown. In most languages, you'd have to check it every time you assign it.

Also, you can declare subtypes which not only define ranges but wall themselves off from each other. If you declare "MonthType" and "DateType" as types, and then ThisMonth and ThisDate as variables, you can't say assign ThisMonth to ThisDate (or vice-versa) without an explicit cast, even if the value stored is within range.

I programmed in Ada more-or-less exclusively for a year, with all the warnings possible turned on, and it did change a bit how I think about programming. I always know, instantly, what type any object is and what its limits are, because I got so used to thinking about those things when using Ada.

Not that it's perfect, or the ultimate, or anything. I had a job where I wrote C only for about 2 years, and that definitely changed how I thought about programming too. When writing C++ I have sense of what the computer is going to have to do to actually run the code.

There's a quote that any language which doesn't change how you think about programming isn't worth knowing. Ada built up my mental macros for making sure my types and values were in order, and for that alone it was worth learning and using for a year.

Re:My problems with Ada

[drxenos]

When is the last time you used Ada? 1) See: Ada.Strings.Unbounded 2) Ada leaves that choice up to the programmer (like C++) (see: pragma controlled). The next version of Ada will have an STL-like library, which will at least reduce the need for GC. 3) See: pragma Export(C, Foo, "foo") and Convention(C, Foo). Some compiles even support CPP in place of C, with automatic translation between C++ classes and exceptions. 5) You should always know the type of data you are dealing with (unless you are writing generics, which still has some limits for safety). 6) Ada's dispatching is based on the actual call being made. No need to mark members has virtual (C++) or to just make them all virtual (Java).

Re:Skill and not language used?

[cmeans]

Or it could simply mean that they way over budgeted for the work that was actually needed to be performed, and poorly spec'd the time it would take to do it. Normally, companies are more conservative with how long it'll take to do something (this helps bring the cost down and increases the likely hood that they'll get the work), thus, the reality tends to extend the deadline. In this case, they might have just been overly generous in their time allotment, and simply fortunate that the client was willing to pay for it.

Re:I used ada....

[SL Baur]

Yeah. The typed I/O stuff was really the pits. It was even more difficult to send arbitrary data across the wire in networked applications (which of course, they all are in C3I - one of Ada's first application domains). Difficult, but not impossible.

Perhaps the best job I ever had was when I was the 900 pound gorilla who vetted commercial Ada compilers. Every so often the boss would come in to my office, drop a package or tape of a commercial Ada compiler on my desk and say, "tell me what you think about this".

I got so frustrated with Verdix Ada at one point because they had potentially the best system, but ignored our (valid) bug reports. After perhaps one beer too many and seeing a remark about VADS on comp.lang.ada, I flamed them. The next day, I got email and a telephone call from a guy at Verdix. After some discussion, I agreed to become a beta tester and if my concerns were addressed to issue a formal public apology on the newsgroup. I did, they did and I did. Unfortunately, the fix was in, the official Unix Ada compiler for the DoD was declared to be Alsys (Ichbiah (Green), Brosgol (Red), duh).

I never met Ichbiah, but I did get to meet Benjamin Brosgol. He participated in Ada training (reeducation sessions) for Software Engineers at the company I worked for. A nice man, but I don't particularly care for the design decisions he makes in language design (and being me, I let him have both barrels - he's remarkably even tempered too).

Alsys was barely usable - the code it produced worked, but even small systems (30k SLOC) took hours to recompile. At one point I was setting up a network test and noticed that one of my embedded message strings was wrong. Rather than doing a painful recompile of the world, I fixed it by editing the binary in Emacs. A couple weeks later, the test was still chugging along (remarkable for Ada stability at the time) and when it was time to give a demo to the highest ranking General in the US Army, the boss lady told me to just leave it running, so I did.

So whatever anyone says about Ada in the 1980s, the view from the trenches was somewhat different. I also have no doubt that the technology probably got quite good in the 1990s. Early adopters always get the rough end of the stick.

Re:I used ada....

[Not The Real Me]

"Likewise, I also used Ada in college."

I too used Ada in college. Ada is a superset of Pascal. It's very similar to Borland's Delphi and Oracle's PL/SQL, which are basically their versions of Object Pascal.

The FAA should've used Java. Then the project would've taken 3x longer and had cost overruns of 400% and/or would've gotten cancelled, like most government projects.

Re:Skill and not language used?

[Samah]

I don't understand why people love dynamic typing so much. I'd much rather the compiler tell me off for misusing a variable than at runtime where it might not crop up until the code is in production. I'm not saying dynamic typing is BAD (I love Lua), just that I don't get why so many people can possibly hate static typing.
Also I don't think you can really label Java as "verbose" when it shares mostly the same the syntax as C++ and C# (unless you assume those to be verbose too).
Having said that, it's not exactly terse, either. :)