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Comment Re:Ada had this in 1995 (Score 2) 262

And that's what makes Ada95 (and subsequent versions) so interesting from a language design perspective. Ada95 built on the Ada83 language (which itself built on Pascal, as well as CLU and other research languages), adding OOP (including supporting concurrent objects in a way that I haven't seen in other "modern" programming languages in this era of multi-core processors). There are design trade-offs, and these are well-documented. If you're interested in such things, the published design team rationale documents (for both Ada83 and Ada95) should be required reading. Ada83: Ada95:

What Ada95 accomplished was to graft a full OO design mechanism (i.e. inheritance) , while preserving type-safety (for scalar types, as well as "objects" or classes), keeping the safety properties (e.g. impossible without unchecked conversion to dereference a null pointer), and providing nearly 100% backwards-compatibility with Ada83. (There were a few inconsistencies, but these were at the edges of the language.)

Oh, and Ada2005 adds support for pre-conditions and post-conditions that matches what Eiffel now provides for defining and enforcing contracts. And it does so while providing the SPARK subset that supports theorem-proving for proof-of-correctness (including concurrent programs), starting with "cannot generate runtime error". See A lot of this grew out of David Luckham's work at Stanford on annotation languages such as ANNA and TSL, see

Comment Re:Ada had this in 1995 (Score 4, Informative) 262

That "piece of shit" is in most modern commercial aircraft these days, as well as the ground ATC systems. Guess maybe you shouldn't fly, then, if that's your opinion, Mr Coward.

There are legitimate criticisms that can be levied against any programming language, as well as against the Ada program. But this comment addresses none of them.

Comment Ada had this in 1995 (Score 3, Informative) 262

Ada95 added OO features including clear mechanisms (enforced by the compiler) on how to get OO design benefits without runtime performance costs or risks for dispatching.

Much of what I've seen in C++ is a response to problems in the original language design, particularly gaps or errors of omission.

Computer Science in the 21st Century seems to be full of stuff we knew about in the '80s and '90s, but forgot.

Comment Re:Tesla not on that list? (Score 1) 535

Pontiac was 'just a brand,' there was really not much difference between Pontiacs and other GM cars (although in my experience renting cars, Pontiac had worse than average fit and finish.) Saturn showed both new auto technologies and a different approach to sales. The original Saturn polycarbonate side panels had a lot of advantages, including no rusting and more ding resistance than metal.

But much more important was Saturn's "no hassle/no negotiation" approach to sales. That alone got Saturn a lot of traffic and sold a lot of cars to a lot of people who were pretty disgusted with the auto industry's "high hassle/high pressure" sales tactics (including me, proud owner of a '94 Saturn. We sold that car with almost 100k miles to a friend for a couple bucks, who put another 40k-50k on it himself.) As the saying goes, "your mileage may vary," particularly if you're driving a VW diesel.

Comment Gmail, Outlook, Yahoo, etc? (Score 1) 106

What about the spam sent by the big email providers? It's a really interesting question what to do when you get -recurring- spam from these. (I get an offer for "Sun Microsystems User Lists" once a month from a chronic spammer sent either through Gmail or now Outlook. I report them to the abuse@xxx, but they keep on coming.) Do you blacklist a chronic spam source, that also has legitimate users? Do you quarantine everything from them, placing the burden on users/administrators to inspect and release legitimate mail from quarantine?

There are certainly lots of IP addresses that can be 'safely' rejected. Unfortunately, the growth of outsourced email makes it increasingly hard to depend on DNS information for sanity checks (e.g. there's an MX or SPF record that associates the "From" domain with the domain actually establishing the SMTP connection.)

Comment Does Ada count as 'little known'? (Score 5, Insightful) 429

Most contemporary aircraft have significant amounts of flight-critical software in Ada, some train control systems use Ada, some air traffic control systems use Ada, and of course there's a lot of Ada in US (and other country's) weapon systems. There's the SPARK subset that has been used for provably correct systems (does your software vendor provide a no-bugs warranty?). And there's production-quality code available under Open Source. (no connection with AdaCore, other than I have lots of friends who work there.) All of my production code after 1980 was written in Ada. There's substantial anecdotal/unpublished evidence that shows large Ada systems have substantially lower life-cycle/software maintenance costs. Your Mileage May Vary, of course.

Submission Google recruits programmers based on their search habits

david.emery writes: Engaget reports that Google is soliciting developers based on Google's analysis of their search habits: Seriously. If you search the right terms often enough, Google might interrupt your quest for knowledge with a question: "You're speaking our language. Up for a challenge?"

Does anyone else find this disturbing?

Comment Re:A significant difference between HW and SW sale (Score 1) 318

Well, I've been running Macs as my primary office automation/desktop (vice development) machine for 29 of the last 30 years, and haven't had these problems. And I routinely get 5 years out of my home Macs (and between 3 and 4 years from the corporate machines.)

Your mileage may vary.

Comment A significant difference between HW and SW sale (Score 4, Interesting) 318

Microsoft, since its only product is software, has to go to great lengths to protect and extend that property base. "Extend" here is Googly data mining.

Apple, on the other hand, makes money by selling you the hardware. The protection is the physical ownership of the device. You might not believe Apple when it says "we don't want your personal information", but you have to respect that they're not depending on either data or software to make the great majority of their revenue.

This may not be a popular opinion, but I trust Microsoft more than Google, Apple -way more- than Microsoft, and the NSA more than any commercial company.

Nonsense. Space is blue and birds fly through it. -- Heisenberg