Slashdot Mirror
The D Programming Language
dereferenced writes: "Walter Bright, author of the
original Zortech C++ Compiler and the free (as in beer) Digital Mars C/C++ Compiler, has posted a draft
specification for a new programming language that he describes as "a successor to C and C++". It seems to me that most of the "new" programming languages fall into one of two categories: Those from academia with radical new paradigms and those from large corporations with a focus on RAD and the web. Maybe its time for a new language born out of practical experience implementing compilers."
I'm afraid I have to disagree. I'm a pretty strong Java advocate, but I still don't feel that it's ready for desktop use because of Swing performance issues. I spoke with several of the engineers that worked on JBuilder while I was at JavaOne this year. They spent a *LOT* of time writing custom classloaders, etc. to make their GUI so snappy. JBuilder is a spectacular example of a well written Java GUI, but I don't know if it would be reasonable to say that just anybody could write something like it in 1/10 the time of some other language.
Now on the server...that's a totally different story. I write server apps all day in Java --- my development times are SLASHED from what they would be in C/C++, or even CGI's. Maintenance and documentation are a breeze, and performance is fabulous. Java really has done great things on the server.
from the overview page...
features to keep:All except the last is contained in Java.
features to drop:This seems to be precisely the parts of C++ that Java also does away with. Furthermore, the C preprocessor is not strictly part of the C language and in fact many other programming projects use cpp for simple cut and paste includes of their favorite language. When I first read about trigraphs, I couldn't wait to try them out to make some extra obfuscated code, but alas the C compiler I was using didn't support them. In fact the lack of standards compliance is one of the main drawbacks to programming in C++ and C. If my Java code compiles on sun's compiler, then I can be assured that it will also compile on any other compiler claiming to compile Java code.
The author also mentions that D will not have any bytecodes. From a strict perspective, the Java programming language and the Java VM are two different standards and just because you typically compile Java code into (confusingly named) Java byte codes, doesn't mean you can't use one without the other. For example, anyone (who is insane) can pick up a copy of the Java Virtual Machine Specification and a hex editor and make some syntactiacally correct class files. More realistically though, java bytecodes are often targets for compiler construction classes. Also, if you use the GNU Java Compiler you can compile programs written in the Java programming language directly into machine code.
While 90% of the description of this language screams Java, there seem to be some of the more useful features of C++ thrown in (typedefs, scope operator, etc.). The only way for this to be successful, is to finish standardizing the language as soon as possible and get a reference compiler for it so it leaves the realm of theoretical vaporware. Perhaps Java might have looked more like this if the language design was revisited. However, Java has lots compilers which are much much more likely to conform to the standard than the C++ equivalents.
I've got an idea... let's hybridize a postfix language like Forth and natural language processing. We can call the new programming language "Yoda." Here's some sample code:
Variable x to 10 be setting.
1 to x you add.
This times 10 you be repeating.
It seems this guy really dosen't like c++. Now, being that he is a compiler implementor, I can certainly understand that! *grin*
Templates and stack instantiation of of objects with semantics [i.e. constructors/destructors] is a royal pain in the a** for compiler writers. In fact, only somewhat more recently is g++ even able to handle templates in a decent way; it took a long time to get it right. C++ was a very ambitious language, hard as hell to implement, but that's what makes it so usefull. Give up templates and multiple inheirantance? He suggests this is a good thing?! D is clearly not a language innovation, he should have called it C--.
Besides, you don't actually have to use such features extensively [or at all, really] in a C++ program. You could always avoid iostream and just #include old stdio.h, for example, only choosing to use classes with constructors for some usefull/neccessariy/labor-saving part of the code, while all the rest of it is essentially no different then C [aside from stricter compile-time type checking, which ANSI C has been moving towards anyway, lately]
This is no innovation.
A few other random points:
Ohh! Garbage collection, you can link to a garbage collecting malloc in a C++ program anyway. [If you really care to look into it, C++ allows a whole range of complex underlying storage classes for custom memory management of different parts of a project.]
Arrays are not first class objects?!
Well, this is true, sort of. But you can choose to use vectors, [or other more efficient representations [such as maps, etc] depending on your data type, and with inlining, they will be as efficient as if they were 'native language syntax' features. You don't even have to use the STL, you can write a custom implementation of dynamicly resizable vectors of your own [with automatic bounds checking and resizing, for example] quite trivially. I did it once, and it took, what, 2 pages of source. That's the power of C++, it's so expressive for implementing custom manipulations of low level data, packaged nicely into classes.
No on stack variables? All data as dynamic references?
Yech. Generally too inefficient. I still suspect that he just dosen't want to tackle the hairness of writing such a complex compiler. Remember, you can use only dynamic memory in C++ easily enough, with garbage collection too.
Overall, I think D is too lenient. I give him an F.
Still, I strongly respect the desire to attempt to implement a novel language. Not that there aren't hundreds out there, but it's a noble effort. Still, publishing without even demo code? Yeesh.
---
the pen is mightier than the sword, the sword is mightier than the court, the court is mightier than the pen.
If, on the other hand, all he wants to do is sell compilers, and therefore he needs to convince the rest of the world of the language's benefit, then fooey.
And for the record, damn, I feel old -- I remember trying to make the Zortech compiler work for an old project of mine circa maybe 1989 or so(?) and having problems. I think at one point or another I might have actually gotten email from Walter. Wow, names from the past. In a conference call yesterday I needed to come up with a secure hashing algorithm and I said "ROT13. If we need extra security we can do it twice." and absolutely no one got it.
Anyway, back on topic: No templates? Oooooo, I have a C++ friend who is gonna be pissed....
duane
"In C++, you can look at your friend's privates."
www.HearMySoulSpeak.com
He's talking about making the compiler do all the work - for instance, there are no headers, as declarations are lifted from the source. For that matter, modules and libararies and source are treated the same. I think that he *might* be talking about features that would require a new object format, and thus a new linker.
I really don't like his ".html" file idea: code inside a html file is compiled by ignoring everything but tagged bits. The concept is to use html to document and compile the code right in the documentation. Personally, I prefer to generate documentation from the code. A language that implements context sensitive comments that can be compiled into various types of documentation would be, IMHO, a very good thing. As it is, systems like doxygen seem to work okay, but if it were built into the language, you could even dump documentation out of modules on the fly. Nifty in an IDE environment, or makefile driven dev when you want to check that version 2.2 of openfoo() does the same thing that 2.1 openfoo() did.
--
Evan
"$30 for the One True Ring. $10 each additional ring!" -- JRR "Bob" Tolkien