yet another +5

If the metric is easier development because the language provides more sugar for certain patterns, how do you justify not using Java or C#?

I can't find in my earlier post where I said I didn't use Java. In fact, I do from time to time. My earlier post was about why I'm such a fan of C++ - and how I can still enjoy all the benefits of both C and C++, even in the same program.

However, I take exception to your implication that Java provides competitive "sugar" to C++. Consider the following example of reading an integer from a file:

C++

int x;
ifstream in_file;
in_file.open("foo.txt");
assert(in_file);
in_file >> x;

Java

int x;
String line;
try {
  FileReader fr = new FileReader("foo.txt");
  BufferedReader br = new BufferedReader(fr);
  line = br.readLine();
  x = parseInt(line);
}
catch (Exception e) {
}

Not more sugar, IMO. Yes, I do realize that Java has to abstract a lot of file I/O due to the fact that it supports multi-byte character sets on dozens of architectures with different byte orders and file systems, thus explaining the syntactic "salt". But, still, even the C version is pretty simple:

C

int x;
FILE* in_file;
in_file = fopen("foo.txt", "r");
assert(in_file);
fscanf(in_file, "%d", &x);

But again, I'm not trying to dismiss Java, only to provide a counter example of where Java fails to provide any programming benefit over C++. Actually, the C and C++ examples above would likely only work on ASCII or UTF-8 filesystems, but Java's UTF-16 support is native to the language¹. So, Java gets to tell C and C++ what "portability" means (even if the programmer has to dig through 67 layers of abstraction to accomplish what he/she set out to do). ;-)

As for C#, well, despite my own thoughts about Microsoft getting in the way, I just don't see why C# even needs to exist. Microsoft was actively marketing Java development suites and compilers in the mid- and late-1990s (Visual J++, anyone?), adding their own APIs and language features, until Sun Microsystems had the guts to stand up to MS and tell them to stop violating the terms of Sun's license (with a successful lawsuit). It was all sour grapes for MS afterwards, so they just had to go run out and create their own Java imitation. C'mon, Microsoft, you already had legions of Visual Basic programmers! Why go out and create a whole new language when there are so many already out there? Was it because Visual Basic wasn't "Java-like" enough?

Not that I think C# is a bad language; it does have some interesting features. But, I get this strange feeling that C# skills will be useless come five years from now, just like Visual Basic skills are in much less demand than they were five years ago.

As for coding C#, well, I abandoned MS Windows four years ago for a single-boot Linux. And the only native C# compiler for Linux I know of is Mono. Which causes anomalous behavior on my Slackware machines. Come to find out Mono has library dependency issues with my current toolchain and dynamic linker. In other words, I experienced DLL HELL in Linux², simply by installing Mono (version 1.24) in Slackware 12. How ironic this is considering I'm trying to write Windows applications in Linux. I suppose the gratuitous DLL hell is all part of the Microsoft "experience" I'm supposed to get whilst writing C# code. No thank you.

I mostly agree with the rest of your post - I do indeed like C's portability (hey, it was one of the core motivations for creating the language to begin with), and I also like its efficiency. I can't say that adding garbage collection to C++ would be worthwhile; Even Bjarne Stroustrup labored over whether to include garbage collection in C++ back in the early 1980s.

My personal thoughts are that garbage collection built-in to the programming language would send several mixed messages to programmers using that language:

• "I don't have to worry about freeing up allocated memory, since the GC will do it for me. This activity doesn't slow down my program, does it?"
• "Since I don't have to worry about keeping track of run-time allocations (why bother? The GC will clean up my mess for me!), I can indulge my code by generously overestimating allocation space. Who cares about the mess to be cleaned up after the party? That's what the GC is for."
• "I've been writing frugal, tidy, and efficient code for years by judiciously managing my run-time allocations. How come all of the sudden I don't have control over this anymore? What if I don't agree with the GC strategy? Can't I disable it completely and manage my own memory usage? After all, I'm quite good at it."

(And Boehm better not be on the line.)

I LOLed at your comment. I downloaded a source tarball several months ago (I forget which program/application) that had a Boehm GC dependency. I thought to myself, C++ doesn't have garbage collection for a reason, but why does this particular project feel that it needs to slather a layer of protection over the code? Are the programmers lazy? Or, do they not know how to use new and delete?

When C++ gets garbage collection and closures, call me.

Perhaps some of your garbage collection needs could be met by using the C++ standard library container classes (e.g., vector, list, deque, etc.). Or, more appropriately stated, your need for a GC to begin with could be eliminated. But, perhaps that's a discussion for another time. I've rambled on long enough, it's been fun pontificating and bloviating (to quote one of my graduate professors). :-)

¹ C++ does have explicit support for multi-byte character sets with its wchar_t type. I don't know what kind of support C has in this regards, or if it supports multi-byte characters at all.

² I'll openly admit that Microsoft unfairly receives the brunt of user frustration over DLL hell when in reality the basic concept of library dependency hell is a Unix creation which predates DLL files by several years.

GC support in the language has one major advantage over not having it: if the compiler and GC
layer cooperate, the language can do type-accurate garbage collection. That's pretty much
impossible with a 'guess if this bit pattern is a pointer' implementation like Boehm.

(But still, why GC in a C/C++ program? Easy: sometimes, the lifespan of allocated regions is
complex enough that you don't want to track it in your own code. A lot of large C/C++ systems
have garbage collectors in them, often hand-rolled. GCC does, for instance, and while its
effect on data locality slowed GCC down a lot, it *also* wiped out huge piles of
otherwise-intractable bugs. In my own coding I find that Apache-style mempools and disciplined
use of ADTs eliminates most of the need for GC while retaining the nice object-lifecycle
benefits of C/C++, so I can use RAII without fear. Losing that pattern in Java is a major
reason why I try to avoid the language: in effect Java eliminates memory leaks only to replace
them with other sorts of resource leak because you can't use RAII to clean them up for you...)

Sorry, completely off topic, I just had to post this.

Python:
int( file("foo.txt").read() )

:-P

How far we've come.. how far.

sorry, I had to :-)

x = File.read("foo.txt").to_i rescue deadParrot

Reading whole file in memory just to parse int from it's first line is very funny :)

You'll need a longer version like this

(File.open('foo.txt') {|f| f.readline}).to_i rescue deadParrot

> C++
> 
> int x;
> ifstream in_file;
> in_file.open("foo.txt");
> assert(in_file);
> in_file >> x;

> C
> 
> int x;
> FILE* in_file;
> in_file = fopen("foo.txt", "r");
> assert(in_file);
> fscanf(in_file, "%d", &x)

Here's something that really bugs me about C++.  Where's the documentation?  With C, "man
fopen" "man assert" "man fscanf" gives me all the info I need.  With C++, I suppose some
manual page for ifstream would be most appropriate, but I don't seem to have it.  Which
package is that in?  Or must I resort to google searches every time?

Of course, even if I did have C++ manpages, deciphering "in_file >> x" still requires that I
track backwards to figure out the types of "in_file" and/or "x" (yay operator overloading!)

See:
http://gcc-ca.internet.bs/libstdc++/doxygen/

I believe some os vendors (debian, I think) package these.

-benjamin

Incidentally, please don't use or encourage use of ‘assert’ for checking for I/O errors or
other can-happen runtime conditions.  Such checks will disappear when compiled with -DNDEBUG
(or conversely make it impractical to compile with -DNDEBUG, thus discouraging use of
assertions), and fail to give a meaningful error message.  That should be ‘if (!in_file) {
perror("foo.txt"); exit(EXIT_FAILURE); }’.

If the metric is easier development because the language provides more sugar for certain patterns, how do you justify not using Java or C#?

Java and C# are using virtual machines and thus are slower. End of story. C is closer to the metal, but suffers from human problem: it's not feasible to generate 10'000 specialization by hand. You need some metaprogramming. If you'll take a look on really fast "C libraries" (like FFTW or ATLAS) you'll find out that while they include bunch of .c files these .c files are not the source! They itself are generated by some automatic process. C++ allows you to do something similar without using yet-another-specialized system (STL and especially boost are big help, but simple template metaprogramming works as well in simple cases). Thus in practice C++ programs written by good programmers are faster then C programs (if you turn of rtti and exceptions, of course). AFAICS this was reason for C++ usage in gold, too.

Of course it's very easy to misuse C++, too...

One point: RTTI and exception handling don't slow down C++ programs anymore, except if
dynamic_cast<> is used or exceptions are thrown, and those are things which if you implemented
them yourself you'd have a lot of trouble making as efficient as the compiler's implementation
(I doubt that you *can* make them as efficient or reliable without compiler support).

I think I need to profile this, then, because exception frames should be 
very nearly free to set up and (non-throw) tear down, certainly not as 
expensive as 15%. This wasn't on an sjlj target, was it? 'cos they're *so* 
last millennium.

Java the programming language doesn't use a virtual machine any more than C does. It happens
to usually be implemented using a virtual machine, but there are native compilers, like gcj.
Furthermore, the coding matters a lot more than the language, and the language can frequently
simplify the coding.