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Walter Bright Ports D To the Mac
jonniee writes "D is a programming language created by Walter Bright of C++ fame. D's focus is on combining the power and high performance of C/C++ with the programmer productivity of modern languages like Ruby and Python. And now he's ported it to the Macintosh. Quoting: '[Building a runtime library] exposed a lot of conditional compilation issues that had no case for OS X. I found that Linux has a bunch of API functions that are missing in OS X, like getline and getdelim, so some of the library functionality had to revert to more generic code for OS X. I had to be careful, because although many system macros had the same functionality and spelling, they had different expansions. Getting these wrong would cause some mysterious behavior, indeed.'"
The opengroup would disagree about Linux being Unix. Someone still has to have it certified and it still wouldn't pass the certification because there are still missing features. Linux is compatible to most of the Unix specification, it is not Unix.
"Not to mention all the idiots who use words like boxen."
Anonymous Coward on Monday August 04, @06:49PM
I was at Berkeley when 4.2BSD was being pulled together, and did some work for the 4.1C release. I was one of the guys who got 386BSD to compile clean in the first place. I had a NeXTstation on my desk for several years. I was the FreeBSD handbook guy for a while. I worked with Tru64 back when it was the only fully 64-bit UNIX. I know what "BSD" and "Mach" are, better than you and better than most of the people who contributed to that Wikipedia page.
you should be aware that this is Slashdot
Yeh, I'm keeping that in mind. Thats why I'm not going to even TRY and explain just how badly you're misreading that Wikipedia page.
Maybe your [sic] right, I can't say.
I can. The gp is wrong on just about every count.
As you already say, if you are very concerned about performance in a situation with lots of small objects you can use structs. Simply ignoring structs because you are too lazy to use them does not make D slow. With a bit of experience and a few rules of thumb it's not hard to choose.
I think maybe you're talking about what is called "scope" now. It allocates the memory for the class on the stack. Yeh, it doesn't cover every possible use case of by-value classes, but it can be a nice optimization.
Yes you use structs when you want an efficient aggregate value type. Classes and structs have different semantics in D. It's pretty easy to choose once you get the hang of it. If you are likely to want to put virtual functions on the thing, make it a class. If you want to pass lots of them around by value, make it a struct. If you can count on your fingers how many instances you will have, make it a class -- the hit from allocation won't matter. There is some gray area in-between, granted, but in practice it's usually pretty clear, and the benefit is that you do completely eliminate the slicing problem by going this route. If you really can't decide you can also write the guts as a mixin and them mix them into both a class and a struct wrapper. Or just write it primarily as a struct, and aggregate that struct inside a class. The use cases that are left after all that are pretty insignificant.
Yeh, well don't try to avoid it, then. It's not as much of a headache as you make it out to be.
D's template system has gone far beyond C++'s. It's even far beyond what C++0x is going to be. Alias template parameters, template mixins, static if, a host of compile-time introspection facilities, the ability to run regular functions at compile-time, type tuples, variadic template parameters. Of these, I believe C++0x is only getting the last one. D metaprogramming is to C++ metaprogramming as C++ OOP is to OOP in C. It takes a technique that the previous language begrudgingly permitted and turns it into one that is actually supported by the language.
Programming in D is nice, but the situation is a bit annoying.
1. Tango vs Phobos. Phobos is the official standard library, but it seems most use Tango. Phobos is also pretty low level compared to Tango.
2. The reference compiler dmd is 32bit only, gdc is outdated and abandoned, and ldc is still alpha status and has missing features. Ldc is quite promising though.
3. D2 is maybe the biggest issue. It has very useful features, such as partial C++ compatibility, but D2 is a moving target and practically no library supports it. It's also unknown when or if ever D2 will become stable. I haven't seen much discussion about it in the newsgroup either.