How to use -H?
I'm trying to create import libraries for use in other projects, using the -H flag, but dmd is still trying to create an executable. How do I specify that all I want are the interface files?
Re: How to use -H?
== Quote from David Nadlinger (s...@klickverbot.at)'s article On 9/3/11 8:17 PM, Sean Eskapp wrote: I'm trying to create import libraries for use in other projects, using the -H flag, but dmd is still trying to create an executable. How do I specify that all I want are the interface files? Does -o- work as you want? David Yes, it does! Turns out the linker errors I was getting were due to Code::Blocks being bad at D.
Re: Public imports with D interface files?
I wasn't including it on the command line; I thought I didn't need to. That
fixed
it, thanks!
== Quote from David Nadlinger (s...@klickverbot.at)'s article
Are you specifying std_ext/typetuple.di or whatever it is called when
compiling the main module? The public import probably triggers creation
of a module constructor as it really creates aliases for the symbols
from the imported module.
David
On 9/4/11 3:17 AM, Sean Eskapp wrote:
I'm compiling a very simple D interface file:
module std_ext.typetuple;
public import std.typetuple
class TypeArray(T...)
{
}
Compiling it as such:
dmd -debug -unittest -D -Dddocs -w -H -o- std_ext/typetuple.d
And including it as such:
import std_ext.typetuple;
void main()
{
TypeArray!(int, double) blah;
}
I get a linker error Symbol Undefined _D7std_ext9typetuple12__ModuleInfoZ
Removing the public import removes this error. How can I fix this?
Is integer overflow defined?
Is integer overflow defined (for instance, as being mod 2^size)? Can I reliably say that -long.min == 0L?
Re: Is integer overflow defined?
== Quote from Timon Gehr (timon.g...@gmx.ch)'s article On 09/01/2011 06:20 PM, Sean Eskapp wrote: Is integer overflow defined (for instance, as being mod 2^size)? I am quite sure that all operations are defined as operations on two's complement integers, which would mean overflow is defined, but I cannot find the respective part of the specification... Can I reliably say that -long.min == 0L? Well no, -long.min == long.min . according to TDPL p53., that fact is defined. (unary minus: -x == ~x+1) Ah, good points, thanks!
struct opEquals does not work with parameter of same type - bug or feature?
I am trying to build a struct with equality testing, using this code:
struct Foo
{
const bool opEquals(Foo f)
{
return true;
}
}
This gives me the error that the parameter should be of type ref const Foo.
Fine.
struct Foo
{
const bool opEquals(ref const Foo f)
{
return true;
}
}
This, however, does not work with code like:
Foo bar()
{
return Foo();
}
assert(Foo() == bar());
function Foo.opEquals(ref const const(Foo) f) const is not callable using
argument types (Foo) and bar() is not an lvalue.
How can I do this?
Re: struct opEquals does not work with parameter of same type - bug or feature?
== Quote from Jonathan M Davis (jmdavisp...@gmx.com)'s article
On Monday, August 29, 2011 22:41:26 Sean Eskapp wrote:
I am trying to build a struct with equality testing, using this code:
struct Foo
{
const bool opEquals(Foo f)
{
return true;
}
}
This gives me the error that the parameter should be of type ref const
Foo. Fine.
struct Foo
{
const bool opEquals(ref const Foo f)
{
return true;
}
}
This, however, does not work with code like:
Foo bar()
{
return Foo();
}
assert(Foo() == bar());
function Foo.opEquals(ref const const(Foo) f) const is not callable using
argument types (Foo) and bar() is not an lvalue.
How can I do this?
http://d.puremagic.com/issues/show_bug.cgi?id=3659
http://stackoverflow.com/questions/6986175/const-ref-and-rvalue-in-d
- Jonathan M Davis
Ah, thanks!
Re: Why aren't function attributes inferred?
== Quote from Timon Gehr (timon.g...@gmx.ch)'s article On 08/20/2011 06:50 PM, Sean Eskapp wrote: Since the compiler can clearly tell when a function is not const, safe, pure, or nothrow, why can't they just be assumed, unless proven otherwise? This sort of inference is already done for function/delegate literals and template functions. It is not done for other functions, because eg. their code is not necessarily available. int foo(int x) pure; // how would you infer purity here? Also, if normal functions would infer those attributes, they would be leaking implementation details all over the place. If a pure implementation would have to be changed to a non-pure one, all code that relied on the undocumented but inferred purity would break. I understand your point about functions with no definition, but your point about normal functions holds true anyway. If I have a pure function foo(), and a function bar() which relies on the purity of foo(), then changing the purity of foo() would break bar()'s internals. Either way, purity should still be inferred at optimization time, where it could really make a difference!
Re: Regarding nothrow and @safe
== Quote from Timon Gehr (timon.g...@gmx.ch)'s article On 08/20/2011 08:18 PM, Sean Eskapp wrote: bearophile: As far as I know they have decided to make memory overflow errors, so they are not exceptions, you can't catch them. Other people will confirm this or not. In this case, how would you go about handling out-of-memory situations? A systems programming language should certainly give the programmer the option to deal with this. You can catch errors, if you want to deal with them. Oops, right. In my mind, exceptions are still anything which can be thrown or caught. I need to remember that it has a more specific meaning in D.
Foreach over tuple of arrays?
I have a tuple of arrays of different types, but want to call a template
function on each element. How would I do this?
void foo(T)(T elem)
{
...
}
I tried like this:
ArrayTuple!(T) data;
void iterate(alias func, uint n)()
{
static if(n T.length)
{
foreach(elem; data[n])
func(elem);
iterate!(func, n + 1)();
}
}
Used like this:
iterate!(foo, 0)();
This doesn't work when passing a delegate as func, however. Is there a way to
circumvent this?
Template struct literals should infer template parameters
If I have something like
struct S(T)
{
T data;
}
I can't make a struct literal with
int mystuff;
someFunc(S(mystuff));
I have to use
int mystuff;
someFunc(S!(int)(mystuff));
Why is this?
Compiling 64-bit code under Windows 7?
I'm trying to compile a very simple file, main.d:
void main()
{
}
Under Windows 7, 64-bit, with out-of-the-box DMD v2.053 installation. I get
this, however:
C:\Users\Me\devl\testdmd -m64 main.d
Internal error: msc.c 268
64-bit two-step compilation on Ubuntu?
I'm trying to get a D2 project to build on Ubuntu through Code::Blocks. Unfortunately, Code::Blocks doesn't allow the simple one-step compilation that is default with dmd, so it does compiling and linking in two separate steps. Unfortunately, this is causing some linker errors, the main one being: /usr/bin/ld: i386 architecture of input file `obj/Debug/main.o' is incompatible with i386:x86-64 output I've tried passing -melf_x86_64 to the linker, and that doesn't change anything. I'm also trying to pass -m64 to the compilation step, and it doesn't work. Help?
Re: 64-bit two-step compilation on Ubuntu?
== Quote from Jonathan M Davis (jmdavisp...@gmx.com)'s article I'm trying to get a D2 project to build on Ubuntu through Code::Blocks. Unfortunately, Code::Blocks doesn't allow the simple one-step compilation that is default with dmd, so it does compiling and linking in two separate steps. Unfortunately, this is causing some linker errors, the main one being: /usr/bin/ld: i386 architecture of input file `obj/Debug/main.o' is incompatible with i386:x86-64 output I've tried passing -melf_x86_64 to the linker, and that doesn't change anything. I'm also trying to pass -m64 to the compilation step, and it doesn't work. Help? First thing I'd try would be to use dmd as the linker. dmd compiles in 32-bit by default. Assuming that you're using dmd 2.052, then you can use -m64 to tell it to compile for 64-bit, at which point linking with gcc should work. Otherwise, you'd need to pass -m32 to gcc when linking (unless you're using ld directly (at which point, I don't know what you do), and I'm not aware of anyone doing that - dmd doesn't). Regardless, if you're linking separately and not using dmd for the linking step, then you need to look at dmd.conf and make sure that you include the linker flags that it does, or your code may not work. In any case, my best suggestion if you can't compile and link in one step would be to just use dmd for both. - Jonathan M Davis How do I use dmd as the linker separately from using it as the compiler? As you can see in my original post, I'm passing -m64 to DMD, but it doesn't seem to be picking it up..
Re: 64-bit two-step compilation on Ubuntu?
== Quote from Jonathan M Davis (jmdavisp...@gmx.com)'s article == Quote from Jonathan M Davis (jmdavisp...@gmx.com)'s article I'm trying to get a D2 project to build on Ubuntu through Code::Blocks. Unfortunately, Code::Blocks doesn't allow the simple one-step compilation that is default with dmd, so it does compiling and linking in two separate steps. Unfortunately, this is causing some linker errors, the main one being: /usr/bin/ld: i386 architecture of input file `obj/Debug/main.o' is incompatible with i386:x86-64 output I've tried passing -melf_x86_64 to the linker, and that doesn't change anything. I'm also trying to pass -m64 to the compilation step, and it doesn't work. Help? First thing I'd try would be to use dmd as the linker. dmd compiles in 32-bit by default. Assuming that you're using dmd 2.052, then you can use -m64 to tell it to compile for 64-bit, at which point linking with gcc should work. Otherwise, you'd need to pass -m32 to gcc when linking (unless you're using ld directly (at which point, I don't know what you do), and I'm not aware of anyone doing that - dmd doesn't). Regardless, if you're linking separately and not using dmd for the linking step, then you need to look at dmd.conf and make sure that you include the linker flags that it does, or your code may not work. In any case, my best suggestion if you can't compile and link in one step would be to just use dmd for both. - Jonathan M Davis How do I use dmd as the linker separately from using it as the compiler? As you can see in my original post, I'm passing -m64 to DMD, but it doesn't seem to be picking it up.. If you pass -c to dmd, it won't link, but will just produce .o files. Otherwise, it'll link the .o files and produce a binary. If you're doing 2 step compilation, then you must be passing -c to dmd for the first step. So, for the second step, just give it the .o files instead of the .d files and don't pass it -c. As for -m64, if you have a version of dmd prior to 2.052, then it only does 32-bit compilation. If you have 2.052, then it should accept -m64 and produce 64-bit .o files, and produce a 64-bit binary when when not using -c. If that doesn't work, then it needs to be reported in bugzilla. - Jonathan M Davis I reinstalled dmd, changed up my compiler flags from global and project-specific to just project specific in Code::Blocks, and removed the unnecessary - melf_x86_64 linker flag, and it seems to have started working. Thanks!
Get single keystroke?
Is there a way to get a single keystroke in D2? Any method I've tried requires pushing Enter before the stroke is registered.
Re: Get single keystroke?
== Quote from Andrej Mitrovic (andrej.mitrov...@gmail.com)'s article
Here's something simpler:
import std.stdio : writefln;
extern(C) int kbhit();
extern(C) int getch();
void main()
{
while(!kbhit())
{
// keep polling
// might use thread.sleep here.
}
writefln(Key hit was %s., getch());
}
What extra linker dependencies does this add?
Re: Get single keystroke?
== Quote from Andrej Mitrovic (andrej.mitrov...@gmail.com)'s article
I believe I've found you a solution:
import std.c.stdio;
import std.c.linux.termios;
extern(C) void cfmakeraw(termios *termios_p);
void main() {
termios ostate; /* saved tty state */
termios nstate; /* values for editor mode */
// Open stdin in raw mode
/* Adjust output channel*/
tcgetattr(1, ostate); /* save old state */
tcgetattr(1, nstate); /* get base of new
state */
cfmakeraw(nstate);
tcsetattr(1, TCSADRAIN, nstate); /* set mode */
// Read characters in raw mode
writefln(The key hit is %s, cast(char)fgetc(stdin));
// Close
tcsetattr(1, TCSADRAIN, ostate); // return to original mode
}
I've tested this under Ubuntu and DMD 2.052 and it works.
Great, thanks!
Re: DMD2 - compiling and linking in separate steps (64-bit)
== Quote from Jonathan M Davis (jmdavisp...@gmx.com)'s article On Friday 18 March 2011 20:49:58 Sean Eskapp wrote: incompatible /usr/lib/../lib/librt.so when searching for -lrt /usr/bin/ld: skipping incompatible /usr/lib/../lib/librt.a when searching for -lrt /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../librt.so when searching for -lrt /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../librt.a when searching for -lrt /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../../lib/libc.so Look at dmd.conf. It includes several flags which are supposed to be passed to the linker - either that or you can use dmd to link rather than using gcc on its own. Personally, I wouldn't bother compiling and linking as separate steps, but if you do, you need to make sure that you either use the flags in dmd.conf or you link with dmd rather than gcc. For the most part, there's no reason to link with gcc, even if you want to link separately. - Jonathan M Davis Hmm.. after linking with all the options in dmd.conf (-L/usr/lib32 -L/usr/lib64 --no-warn-search-mismatch --export-dynamic -lrt), I still get /usr/bin/ld: skipping incompatible /home/me/devl/sfml2/bindings/d/lib/libdsfml-system.a when searching for -ldsfml-system /usr/bin/ld: cannot find -ldsfml-system /usr/bin/ld: skipping incompatible /home/me/devl/sfml2/bindings/d/lib/libdsfml-graphics.a when searching for -ldsfml-graphics /usr/bin/ld: cannot find -ldsfml-graphics /usr/bin/ld: skipping incompatible /home/me/devl/sfml2/bindings/d/lib/libdsfml-audio.a when searching for -ldsfml-audio /usr/bin/ld: cannot find -ldsfml-audio /usr/bin/ld: skipping incompatible /home/me/devl/sfml2/bindings/d/lib/libdsfml-window.a when searching for -ldsfml-window /usr/bin/ld: cannot find -ldsfml-window collect2: ld returned 1 exit status Now, I compiled libdsfml-system.a myself, and I know they're 64-bit, so this implies ld still isn't recognizing that I want 64-bit executables.
Buliding DSFML2? (64-bit Linux)
I've been trying for weeks to build the D bindings of SFML2, but with little success. The main issue is that I get a myriad of linker errors (documented at http://www.sfml-dev.org/forum/viewtopic.php?p=28345#28345), but I can't figure out what linking options would solve them. Can anybody shed some light on this?
Re: Buliding DSFML2? (64-bit Linux) (New info)
== Quote from Jonathan M Davis (jmdavisp...@gmx.com)'s article On Friday, March 18, 2011 17:56:44 Sean Eskapp wrote: I've been trying for weeks to build the D bindings of SFML2, but with little success. The main issue is that I get a myriad of linker errors (documented at http://www.sfml-dev.org/forum/viewtopic.php? p=28345#28345), but I can't figure out what linking options would solve them. Can anybody shed some light on this? Just glancing at it, it looks like you might be missing pthreads, though that would be pretty weird. You don't normally need to specify - lpthread. But those symbols sure look like they're likely pthread-related. - Jonathan M Davis I've tried -lpthread and -lm, and neither seemed to help. Is it possible there are platform issues, since D (to my knowledge) is 32- bit, and I'm 64-bit?
Re: GDC with D2?
== Quote from Jonathan M Davis (jmdavisp...@gmx.com)'s article On Friday, March 18, 2011 19:00:40 Sean Eskapp wrote: Does GDC support D2? Yes. It's also fairly up-to-date now too, I believe (though it is still a bit behind dmd as I understand it - at least as farn as Phobos goes). I don't use anything other than dmd though, so I'm not sure of gdc's exact state. There _is_ a fairly up-to-date D2 version though. - Jonathan M Davis Great, thanks!
Re: Building DSFML2? (64-bit Linux)
== Quote from Jonathan M Davis (jmdavisp...@gmx.com)'s article On Friday, March 18, 2011 18:58:49 Sean Eskapp wrote: == Quote from Jonathan M Davis (jmdavisp...@gmx.com)'s article On Friday, March 18, 2011 17:56:44 Sean Eskapp wrote: I've been trying for weeks to build the D bindings of SFML2, but with little success. The main issue is that I get a myriad of linker errors (documented at http://www.sfml-dev.org/forum/viewtopic.php? p=28345#28345), but I can't figure out what linking options would solve them. Can anybody shed some light on this? Just glancing at it, it looks like you might be missing pthreads, though that would be pretty weird. You don't normally need to specify - lpthread. But those symbols sure look like they're likely pthread-related. - Jonathan M Davis I've tried -lpthread and -lm, and neither seemed to help. Is it possible there are platform issues, since D (to my knowledge) is 32- bit, and I'm 64-bit? Well, as of dmd 2.052, if you pass -m64 to dmd, it'll compile in 64-bit on Linux, but if you don't pass it -m64 (or if you explicitly pass it -m32), it will compile in 32-bit. And if it's compiling in 32-bit, then you need the 32- bit versions of whatever libraries that you're using. pthread is one of them. So, if you don't have a 32-bit version of pthread installed, then that would explain it. - Jonathan M Davis Perfect, thanks!
DMD2 - compiling and linking in separate steps (64-bit)
I'm trying to use DMD through an IDE, but I'm getting stumped trying to create 64-bit executables under Linux. I can get everything compiled fine, using the -m64 compiler flag, but I can't get it to link. Here's the error list: /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../../lib/libphobos2.a when searching for -lphobos2 /usr/bin/ld: skipping incompatible /usr/lib/../lib/libphobos2.a when searching for -lphobos2 /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../libphobos2.a when searching for -lphobos2 /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../../lib/libm.so when searching for -lm /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../../lib/libm.a when searching for -lm /usr/bin/ld: skipping incompatible /usr/lib/../lib/libm.so when searching for -lm /usr/bin/ld: skipping incompatible /usr/lib/../lib/libm.a when searching for -lm /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../libm.so when searching for -lm /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../libm.a when searching for -lm /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../../lib/libpthread.so when searching for -lpthread /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../../lib/libpthread.a when searching for -lpthread /usr/bin/ld: skipping incompatible /usr/lib/../lib/libpthread.so when searching for -lpthread /usr/bin/ld: skipping incompatible /usr/lib/../lib/libpthread.a when searching for -lpthread /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../libpthread.so when searching for -lpthread /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../libpthread.a when searching for -lpthread /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/libgcc.a when searching for -lgcc /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/libgcc.a when searching for -lgcc /usr/bin/ld: cannot find -lgcc /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../../lib/librt.so when searching for -lrt /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../../lib/librt.a when searching for -lrt /usr/bin/ld: skipping incompatible /usr/lib/../lib/librt.so when searching for -lrt /usr/bin/ld: skipping incompatible /usr/lib/../lib/librt.a when searching for -lrt /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../librt.so when searching for -lrt /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../librt.a when searching for -lrt /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../../lib/libc.so when searching for -lc /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../../lib/libc.a when searching for -lc /usr/bin/ld: skipping incompatible /usr/lib/../lib/libc.so when searching for -lc /usr/bin/ld: skipping incompatible /usr/lib/../lib/libc.a when searching for -lc /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../libc.so when searching for -lc /usr/bin/ld: skipping incompatible /usr/lib/gcc/x86_64-linux- gnu/4.4.5/../../../libc.a when searching for -lc collect2: ld returned 1 exit status How do I use ld to link 64-bit D executables?
Re: DMD on linux? (more problems)
== Quote from Jesse Phillips (jessekphillip...@gmail.com)'s article Sean Eskapp Wrote: I'm still having issues with the linux dmd. Here's the relevant part of the output: ... function func function func gcc Nullimorphism.o -o Nullimorphism.exe -g -m32 -l -Xlinker - L/usr/lib32 -Xlinker -L/usr/lib64 -Xlinker --no-warn-search- mismatch -Xlinker --export-dynamic -lrt -lphobos2 -lpthread -lm /usr/bin/ld: cannot find -l-Xlinker collect2: ld returned 1 exit status --- errorlevel 1 make[1]: *** [all] Error 1 make[1]: Leaving directory ... Any help is appreciated. I think the part LD is tripping up on is -m32 -l -Xlinker So it seems you are calling dmd incorrectly or modified dmd.conf incorrectly as there is no argument after -l so LD thinks you want to link against lib-Xlinker. Oops yeah, there was some obsolete in the makefile in my project. Don't know how it managed to compile on windows, though.. Thanks, though, problem solved.
DMD on linux?
I'm trying to work with D on Ubuntu, but I keep having this issue: ... function func function func gcc Nullimorphism.o -o Nullimorphism.exe -g -m32 -l -Xlinker -L/usr/bin/../lib32 -Xlinker - L/usr/bin/../lib64 -Xlinker --no-warn-search-mismatch -Xlinker --export-dynamic -lrt - lphobos2 -lpthread -lm /usr/bin/ld: cannot find -l-Xlinker /usr/bin/ld: cannot find -lphobos2 collect2: ld returned 1 exit status --- errorlevel 1 make[1]: *** [all] Error 1 ... I downloaded the DMD v2.052 ZIP from the download page, extracted the linux/bin folder into /usr/bin, the linux/lib64 folder into /usr/lib64, and the src folder into /usr/src. Can somebody please help?
Re: DMD on linux?
== Quote from Jonathan M Davis (jmdavisp...@gmx.com)'s article On Wednesday, March 02, 2011 13:52:29 Sean Eskapp wrote: I'm trying to work with D on Ubuntu, but I keep having this issue: ... function func function func gcc Nullimorphism.o -o Nullimorphism.exe -g -m32 -l -Xlinker -L/usr/bin/../lib32 -Xlinker - L/usr/bin/../lib64 -Xlinker --no-warn-search-mismatch -Xlinker --export-dynamic -lrt - lphobos2 -lpthread -lm /usr/bin/ld: cannot find -l-Xlinker /usr/bin/ld: cannot find -lphobos2 collect2: ld returned 1 exit status --- errorlevel 1 make[1]: *** [all] Error 1 ... I downloaded the DMD v2.052 ZIP from the download page, extracted the linux/bin folder into /usr/bin, the linux/lib64 folder into /usr/lib64, and the src folder into /usr/src. Can somebody please help? 1. I never bother installing the zip anywhere. If you just unzip it and add /path/to/unzipped/dmd2/linux/bin to your path, then you should be fine. I don't see any real reason to actual try and install dmd into your system folders (though you obviously can if you want to). 2. Assuming that you _do_ move files around, you need to adjust your dmd.conf so that it points to the appropriate places. 3. If you just moved files around, then you might not _have_ a dmd.conf, and you're doubly screwed. Take a look at the documentation page for dmd on linux: http://www.digitalmars.com/d/2.0/dmd-linux.html It's slightly out of date, since with the last release, 64-bit support was added, and the 32-bit version of libphobos.a is in /path/to/unzipped/dmd2/linux/lib32 and the 64-bit version is in /path/to/unzipped/dmd2/linux/lib64, but the instructions should be correct otherwise. You need to make sure that dmd is on your path and that a version of dmd.conf which points to the place where libphobos2.a is is in one of the places that dmd looks for dmd.conf (as described on that page). Also, make sure that you're using a dmd.conf based on the most recent version, or you could be missing necessary linker flags. - Jonathan M Davis Hmm my dmd.conf seems fine, but since the .deb has been updated, I can just use that. Thanks!
DMD on linux? (more problems)
I'm still having issues with the linux dmd. Here's the relevant part of the output: ... function func function func gcc Nullimorphism.o -o Nullimorphism.exe -g -m32 -l -Xlinker - L/usr/lib32 -Xlinker -L/usr/lib64 -Xlinker --no-warn-search-mismatch -Xlinker --export-dynamic -lrt -lphobos2 -lpthread -lm /usr/bin/ld: cannot find -l-Xlinker collect2: ld returned 1 exit status --- errorlevel 1 make[1]: *** [all] Error 1 make[1]: Leaving directory ... Any help is appreciated.
Re: Checking if something is a template specialization?
== Quote from Lars T. Kyllingstad (public@kyllingen.NOSPAMnet)'s article
On Fri, 18 Feb 2011 02:02:51 +, Sean Eskapp wrote:
If I have
class Bar(T)
{
}
void foo(Y)()
{
...
}
Is there a way to check inside foo() that Y is in some way an
instantiation of Bar? Is there a way to find WHICH instantiation it is?
void foo(Y)()
{
static if (is(Y Z == Bar!Z))
{
// Here, Z is now an alias to whichever type Bar is
// instantiated with.
}
else
{
// Z is invalid here.
}
}
Perfect, thanks!
Finding out if T is a specialization of another template
I was given this code, to check if Y is a specialization of Bar. How does it
work?
class Bar(T)
{
}
void foo(Y)()
{
static if (is(Y Z == Bar!Z))
{
// Here, Z is now an alias to whichever type Bar is
// instantiated with.
}
else
{
// Z is invalid here.
}
}
Re: Finding out if T is a specialization of another template
== Quote from Lars T. Kyllingstad (public@kyllingen.NOSPAMnet)'s article
On Fri, 18 Feb 2011 17:16:02 +, Sean Eskapp wrote:
I was given this code, to check if Y is a specialization of Bar. How
does it work?
class Bar(T)
{
}
void foo(Y)()
{
static if (is(Y Z == Bar!Z))
{
// Here, Z is now an alias to whichever type Bar is //
instantiated with.
}
else
{
// Z is invalid here.
}
}
I'm not sure what you mean by how does it work. If it's the is()
expression you're wondering about, it's documented here:
http://www.digitalmars.com/d/2.0/expression.html#IsExpression
-Lars
Ah, yes. I'd checked the is documentation, but whenever I tried using that is
expression outside of an if statement, it complained about my usage, so I
assumed
it had something to do with if statements.
Verify tuple is a tuple of class objects?
Is there a way to run a template at compile time, without using a member?
What I'm trying to do is verify that every element of a tuple is a class type,
and so far, I've been doing this:
template VerifyTuple(Type, Types...)
{
static assert(is(Type : Object), Type.stringof ~ is not a class
type.);
static if(Types.length == 0)
alias void dummy;
else
alias VerifyTuple!(Types).dummy dummy;
}
and to use it, I have to do this:
class Foo(T...)
{
alias VerifyTuple!(T).dummy dummy;
}
Is there any way to just run the template, without bothering to use the
dummy aliases?
struct opEquals bug
Has this been reported?
struct A
{
int x;
A foo()
{
return A(x);
}
const bool opEquals(ref const A other)
{
return (x == other.x);
}
}
void main()
{
auto a = A(5);
assert(a == a.foo); // Error
assert(a.foo == a); // OK
}
The first assert fails to compile because a.foo isn't an lvalue, but the
second assert compiles fine. However, the language documentation states that
...the expressions a.opEquals(b) and b.opEquals(a) are tried. If both resolve
to the same opEquals function, then the expression is rewritten to be
a.opEquals(b).
If one is a better match then the other, or one compiles and the other does
not, the one is selected.
Otherwise, an error results.
In this case, a.opEquals(b) doesn't compile, but b.opEquals(a) does, so it
should be selected.
Checking if something is a template specialization?
If I have
class Bar(T)
{
}
void foo(Y)()
{
...
}
Is there a way to check inside foo() that Y is in some way an instantiation of
Bar? Is there a way to find WHICH instantiation it is?
Double-dispatch
I remember in C++, I had to do double-dispatch using the visitor pattern. This
is cumbersome, just because each subclass has to have the exact same
singly-dispatched code that looks like:
void dispatch(Base other)
{
other.dispatch(*this);
}
Is there a nicer way to do this in D, or am I stuck with the same thing?
Re: Double-dispatch
== Quote from bearophile (bearophileh...@lycos.com)'s article Sean Eskapp: Is there a nicer way to do this in D, or am I stuck with the same thing? Andrei has recently said no one needs double dispatch (in D) :-) So Andrei will be interested in your use case. Bye, bearophile The age-old collision handling problem is how I'm using it.
Opt-out polymorphism?
Is there a way to specify that a function is nonvirtual, but can still be
overriden in base classes? e.g.
class A
{
void foo()
{
writeln(A);
}
}
class B : A
{
void foo()
{
writeln(B);
}
}
void main()
{
(new A).foo();
(new B).foo();
}
Should output:
A
B
Is there a way to do this?
Why no struct default constructors?
With the removal of scope classes, the only way of which I know to use RAII objects is to use structs. This is fine, but structs aren't allowed default constructors! Why is this?
Re: Why no struct default constructors?
== Quote from Jonathan M Davis (jmdavisp...@gmx.com)'s article On Saturday 12 February 2011 10:48:04 Sean Eskapp wrote: With the removal of scope classes, the only way of which I know to use RAII objects is to use structs. This is fine, but structs aren't allowed default constructors! Why is this? It's because they have to have an init property. _All_ types have an init property. It's what they're default initialized to. For bool, it's false. For integral types, it's 0. For floating point types, it's NAN. Etc. For classes, that's null, so they can have default constructors just fine. However, for structs, it must be what the struct's member variables are directly initialized to. If you could have an arbitrary default constructor, then you'd have the problem of it throwing exceptions as well as it trying to run functions which could only be run at runtime. The struct's init value must be known at compile time, and it must _always_ be the same. So, it can't involve any functions which would have to be run at runtime, and it can't involve anything that would result in differing values betwen runs of the default constructor. There has been some discussion of allowing structs to have limited default constructors, but they would still disallow most of the kinds of things that people would want to do with a default constructor. init _must_ be known at compile time. So, its value is taken from the value that a struct gets when all of its member variables have been directly initialized (or default initialized) and no constructor has been called. It _can_ be a bit annoying at times, but it's either that or allow undefined struct values, which would be a big problem and go against D's philosophy on default initialization. Since you can't have a default constructor, what you do instead is define a static opCall() function for the struct and use that. Then you construct a struct (with the name S in this case) like so: auto s = S(); You're still stuck with the init state if you do S s; or if you're dealing with structs in an array and the like (since they're all default constructed to the struct's init property). But you can do RAII just fine. Personally, I _always_ use this syntax when declaring struct variables: auto S = S(); So, the situation isn't exactly ideal, but we're kind of stuck, given the various constraints that we have to work with. - Jonathan M Davis Alright, thanks for clearing that up!
Invoke garbage collector?
I'm having an unfortunate DSFML issue, where failing to free objects like Images or Sprites causes exceptions to eventually be thrown. Calling the built-in member dispose() causes access violations, so I assume it's not for programmer use. However, I need the resources to be freed more quickly than the GC is apparently doing (I assume the Images and Sprites are eventually cleaned up), so is there a way to invoke a GC cleanup in some way?
Re: Invoke garbage collector? (Scoped Instances)
== Quote from Trass3r (u...@known.com)'s article However, I need the resources to be freed more quickly than the GC is apparently doing You could use scoped instances if you need to clean them up soon after creation. To my knowledge, these are being removed from the language, and so, could only be used in the short-term.
Debugging D?
Are debug symbols compiled with -gc stored in a separate file? Visual Studio refuses to debug my things, and windbg seems to be remarkably unhelpful.
Re: Debugging D?
== Quote from Robert Clipsham (rob...@octarineparrot.com)'s article On 06/02/11 20:29, Sean Eskapp wrote: Are debug symbols compiled with -gc stored in a separate file? Visual Studio refuses to debug my things, and windbg seems to be remarkably unhelpful. I suggest you take a look at VisualD if you're using visual studio, it will handle converting debug info so that visual studio can understand it, and give you some intellisense. http://www.dsource.org/projects/visuald I'm using VisualD already, but the project is configured using Makefiles, and I don't want to go through the hassle of changing project configs in two locations. Is there any way to still get Visual Studio debugging information if it's a makefile project?
DSFML
I've been unable to build ANYTHING with DSFML, either by using the version on the download page, or by using the version in the SVN repository. Has anybody else had this trouble? Can I just not use DSFML with DMD v2.051?
SFML in D?
Are there wrappers of some kind for SFML in D?
Opt-out closures
I get errors when working with nested functions and structs or scoped classes, because closures can't be used with anything with scoped destruction. This makes complete sense, but I don't even want the closure functionality of these nested functions. Personally, I would like to be able to opt-out of the closure functionality of nested functions: if the enclosing function exits, and a nested function thereof is called, then a segfault would occur when it tried to access the stack of its enclosing function; however, access of scoped-destruction variables from an enclosing-scope function would be fine. Thoughts? The not-being-able-to-access-scoped-destruction-variables thing is really getting to me, since one of the main driving features I like about D is the ability to use anonymous and nested functions.
Re: Opt-out closures
== Quote from Jonathan M Davis (jmdavisp...@gmx.com)'s article On Sunday 23 January 2011 06:36:27 Sean Eskapp wrote: I get errors when working with nested functions and structs or scoped classes, because closures can't be used with anything with scoped destruction. This makes complete sense, but I don't even want the closure functionality of these nested functions. Personally, I would like to be able to opt-out of the closure functionality of nested functions: if the enclosing function exits, and a nested function thereof is called, then a segfault would occur when it tried to access the stack of its enclosing function; however, access of scoped-destruction variables from an enclosing-scope function would be fine. Thoughts? The not-being-able-to-access-scoped-destruction-variables thing is really getting to me, since one of the main driving features I like about D is the ability to use anonymous and nested functions. If a nested function is marked as static, then it results in a function rather than a delegate. Of course, that means that you can't access the enclosing scope, but if you don't care about that, then just use static. - Jonathan M Davis I want to be able to access the enclosing scope, but NOT after the function has exited; I should have the option of accessing the enclosing scope, but at the cost of making my delegate not a closure.
Re: Opt-out closures
== Quote from bearophile (bearophileh...@lycos.com)'s article
Sean Eskapp:
I want to be able to access the enclosing scope, but NOT after the function
has
exited; I should have the option of accessing the enclosing scope, but at
the cost
of making my delegate not a closure.
It seems a worth thing to ask for. A possible syntax (not currently
supported):
void foo() {
scope void bar() {}
}
Bye,
bearophile
That looks like one of the best options syntax-wise. Nice!
Re: Opt-out closures hack
== Quote from Torarin (torar...@gmail.com)'s article
2011/1/23 Sean Eskapp eatingstap...@gmail.com:
I want to be able to access the enclosing scope, but NOT after the function
has
exited; I should have the option of accessing the enclosing scope, but at
the cost
of making my delegate not a closure.
Until we have a dedicated syntax for it, I think you can use this hack:
import std.traits;
auto scopeDelegate(D)(scope D d) if (isDelegate!D)
{
return d;
}
int main()
{
StructWithDtor s;
trustedFunction(scopeDelegate({s.a = 5;}); // No heap allocation
}
Torarin
Yup, works great with everything I've tried! Thanks.
How to wrap SDL?
I'm using the Derelict SDL bindings, and I'm wrapping some parts of SDL in my own objects. Originally, I was using classes, but this caused a number of errors when the program exited, since Derelict unloaded itself before the garbage collector took care of destructing my classes. So I switched to scope classes. This works fine, but I've been told they're being removed from the language (?) and to use structs instead for RAII. How should I be wrapping this SDL stuff?
Re: How to wrap SDL?
== Quote from Andrej Mitrovic (andrej.mitrov...@gmail.com)'s article
You can use scoped!() from std.typecons:
import std.stdio;
import std.typecons;
class A
{
~this()
{
writeln(A destructor);
}
}
void foo()
{
auto a1 = scoped!A();
}
void main()
{
foo();
writeln(exiting..);
}
You must not escape a reference to the object outside of the foo()
scope. Note that you will get a runtime error if you try to do
something like this:
import std.stdio;
import std.typecons;
class A
{
~this()
{
writeln(A destructor);
}
}
auto foo()
{
auto a1 = scoped!A();
return a1;
}
void main()
{
auto result = foo();
writeln(exiting..);
}
Illegal call to Scoped this(this)
A destructor
core.exception.AssertError@std.typecons(2506): Assertion failure
But these can't be passed to functions either, meaning I can't pass a Screen,
Text, or Font wrapper around, all of which I use in my project!
Structs with pointers?
Why doesn't this code work?
struct Bar
{
int* x;
}
void foo(Bar a) {}
void main()
{
const a = Bar();
foo(a);
}
But replacing int* with some other type works fine? Even if a write a postblit
function for Bar, it still fails to compile.
Re: Structs with pointers?
== Quote from Sean Eskapp (eatingstap...@gmail.com)'s article
Why doesn't this code work?
struct Bar
{
int* x;
}
void foo(Bar a) {}
void main()
{
const a = Bar();
foo(a);
}
But replacing int* with some other type works fine? Even if a write a postblit
function for Bar, it still fails to compile.
Nevermind, I realized it's because constness is transitive in pointers. A const
struct with a pointer member has a const pointer member, and those can't be
implicitly cast to non-const pointer members.
Re: Structs with pointers?
== Quote from bearophile (bearophileh...@lycos.com)'s article
Sean Eskapp:
Nevermind, I realized it's because constness is transitive in pointers. A
const
struct with a pointer member has a const pointer member, and those can't be
implicitly cast to non-const pointer members.
Uhm, the struct having a pointer is not important. In theory this too can't
compile:
struct Bar {}
void foo(Bar b) {}
void main() {
const b = Bar();
foo(b);
}
Is this another compiler bug?
Bye,
bearophile
No, that compiles fine. Because the struct owns a pointer, the const struct
owns a
const pointer. When copying a const-struct to a non-const struct, this means you
must cast a const-pointer to a non-const pointer, which shouldn't be allowed.
How to use structs for RAII?
It was recommended to me to use structs for RAII instead of scope classes, since scope is being removed (?). However, since default-constructors for structs can't exist, how does one do this?
Re: How to use structs for RAII?
== Quote from bearophile (bearophileh...@lycos.com)'s article Sean Eskapp: It was recommended to me to use structs for RAII instead of scope classes, since scope is being removed (?). However, since default-constructors for structs can't exist, how does one do this? Inside the ~this() you may put code, to deallocate resources you have allocated in an explicit constructor (or in some creation method). Is this enough? Bye, bearophile By explicit constructor, I assume you mean one with parameters? I guess that's alright.
assert vs enforce?
What's the difference between assert and enforce in D?
Re: How to use structs for RAII?
Actually this becomes rather annoying, since I can't use any closures on the object. Stupidly, I can still use closures with an object which is deleted at the end of the function.
Re: assert vs enforce?
Ah, that clears it up. Thanks!
Garbage-collected structs vs garbage-collected classes
When I was using a class to wrap SDL functions and structs, I would have a problem that Derelict would unload before the garbage-collector cleaned up my classes, resulting in errors when these classes destructed and tried to call SDL functions in the process. However, the exact same code using structs to wrap instead of classes does not produce these errors. For example, rather than using scope screen = new Screen(800, 600) where Screen is a scope class, I'm using auto screen = new Screen(800, 600) where Screen is a struct. This also provides me the advantage of being able to use delegates which use screen. Is there a reason for this?
Is it true scope declarations are being removed?
Someone mentioned to me that scope declarations, e.g.
scope class A{}
or
scope A myNewObject;
are being removed from the language. Is this true? If so, how will RAII-type
classes be implemented?
Type-qualified functions?
How does one avoid code duplication in a snippet code like this:
class A{}
void foo(const A, void delegate(const A) fn)
{
// some stuff
// ...
// ...
}
void foo(A, void delegate(A) fn)
{
// exact same stuff, with different qualifiers
// ...
// ...
}
Re: Type-qualified functions?
templates:
void foo(T)(T, void delegate(T) fn)
{
}
This parameterizes foo based on T, which could be A, const A, or int, or
whatever works to compile the function.
What if the parameters are more general, for instance the first parameter is
always a Foo, the second is a delegate which takes a Foo.Bar, but they're always
qualified the same way?
const-typed class does not have const members
The following code yields results as commented.
import std.stdio;
class A
{
int b;
}
void main()
{
const A a = new A;
writeln(typeof(a).stringof); // const(A)
writeln(typeof(a.b).stringof); // const(int)
writeln((const A).stringof); // const(A)
writeln(typeof((const A).b).stringof); // int
}
Given this information, how do I work around this in templates? I'd like a
template which can type its params based on members of T, for instance:
void foo(T)(T x, typeof(T.member) y)
but this will yield non-const second parameters even if T is const. Help
anybody?
Casting between delegates with qualified value type parameters
Delegates cannot be cast from one type to another, even if the only difference
in type is the qualifiers on value type parameters. However, the same code
works fine with functions instead of delegates, as such:
import std.stdio;
void foo(void function(int) bar)
{
bar(5);
}
void foobar(void delegate(int) bar)
{
bar(5);
}
void main()
{
foo (function(int i) { writeln(i); }); // OK
foo (function(immutable int i) { writeln(i); }); // OK
foobar(delegate(int i) { writeln(i); }); // OK
foobar(delegate(immutable int i) { writeln(i); }); // error
}
Is there a reason for this, or is it a bug?
Struct constructors
In code like this:
import std.stdio;
struct foo
{
int val;
static immutable bar = foo(1);
this(int val)
{
this.val = 50;
}
}
void main()
{
writeln(foo.bar.val);
}
The user-defined struct constructor is not called, because it's overridden by
a built-in constructor which treats it like an initializer list. Shouldn't
constructors in structs either generate errors/warnings, or work as they would
appear to?
Re: Struct constructors
That looks like a similar issue. Thanks!
const vs immutable
In cases where they are the same, for instance declaring: const int x = oldX + 5; vs immutable int x = oldX + 5; Or in non-class, non-array function parameters, does it make a difference which is used?
in vs const
For function parameters where the scope keyword doesn't matter (e.g. intrinsic types, many classes, structs, etc.), does in produce different code from const?
How to use std.bind?
I used to use boost::bind all the time, but std.bind has me stumped, as I keep
getting static asserts with a cryptic argument has no parameters message. At
this point, the code is just:
class Foo
{
void bar(int i) { writeln(i); }
}
void main()
{
auto foobar = new Foo;
bind(foobar.bar, 5)();
}
I've tried a myriad of different ways, but keep coming up with the same error.
Using bindAlias gives me an error that std.bind.bindAlias(alias FT) is not a
function template.
I'm using DMD v2.051 on a Windows platform. Help anybody?
Re: Using template typetuples?
That looks like it.. only, it's not working:
void main()
{
TypeTuple!(int, int) foo;
foo[0] = 1;
foo[1] = 2;
double MakeStuff(in int bar)
{
return cast(double)bar;
}
auto foobar = staticMap!(MakeStuff)(foo);
}
This fails compilation with the error Error: function expected before (), not
()
of type ()
Re: Using template typetuples?
Nevermind, I see my error. Thank you!
Casting between tuples
I have a variable of type TypeTuple!(int, int), and I want to convert all its elements into a variable of type TypeTuple!(string, string). Is there a way to do this? Using a loop fails compilation with Error: Integer constant expression expected instead of i. I'd also like to be able to convert from arrays of base classes (static size) to TypeTuples of derived classes. static for doesn't work either. Is there a way to do this.. without a recursive template function?
Forward declaration error with auto
Referring to functions declared later inside a module with return type auto causes an error, but not when the return type is explicitly declared. The same goes for calling functions in other modules with return type auto. Is this supposed to happen?
Recommendation: functional keyword
I recommend that there be a functional keyword, which when applied to functions, would not allow them to modify existing data, or call impure functions. This would imply pure. Thoughts?
Re: Recommendation: functional keyword
Functional functions could not modify ANY data, including explicitly allocating variables. Although, come to think of it, this wouldn't imply pure, as they should still be allowed to read global data and call impure functions.
Re: Recommendation: functional keyword
It's a programmer contract, nothing more. It forces the code to be functional, not procedural. Just like const and @safe are simply programmer contracts, functional would mean no explicit stack allocation, except that allocated in called functions.
Is this a bug?
This code works fine:
int[] arr = [ 1, 2, 3, 4, 5 ];
auto myMax = function int(int a, int b) { return (a b) ? a : b; };
auto biggest = reduce!(myMax)(arr);
But passing the function literal directly to reduce causes an error. Is this
intentional?
How to convert Map to array?
I'm trying to use the array() function in std.array to convert a transformed array using map (std.algorithm) back to a dynamic array, from a Map. I keep getting a cryptic error object.except...@c:\Program Files (x86)\D\dmd2\windows\bin\..\..\src\phobos\std\ algorithm.d(426): Cannot reduce an empty range w/o an explicit seed value.. Am I misunderstanding how this is supposed to work?
Re: What's wrong with this code? (OP)
Tomek got it right. Fixed by copying the objects, rather than using pointers. Thanks!
Module is private when calling function
I have two modules:
foo.d:
public void Foo(int x) {}
private void Foo(string x) {}
private void Bar(string x) {}
public void Bar(int x) {}
main.d:
import foo;
void main()
{
Foo(5); // OK
Foo(Hello); // error: function is private (correct)
Bar(5); // error: module is private (incorrect)
Bar(hello); // error: function is private (correct)
}
With the errors demonstrated. When a public function is denoted below a
private function, the private function seems to intercept the overload. Is
this supposed to happen?
Ref function pointers?
Is there a way to create a function pointer which returns a reference? In all the ways I've tried it, my return value becomes not an lvalue.
@safe functions
This is either a compiler bug, or outdated language documentation, but I'm
having some freedom with @safe functions:
* No casting from a pointer type to any type other than void*.
* No modification of pointer values.
* No taking the address of a local variable or function parameter.
I've attached code which does all three of these things, which compiles and
runs.
Inline assembler was an error, as well as casting from integer to a pointer
type, but I didn't test anything else.
I'm using dmd2.exe as my compiler.
begin 644 main.d
M:6UP;W)T('-T9YS=1I;SL-@T*0'-a...@=f]i9!F;V\H:6YT('@I#0I[
M#0H):6YT($[#0H):6YT*B!Y(#T@)F$[(\O('1A:VEN9R!A91R97-S(]F
M(QO8V%L('9AFEA8FQE#0H)8VAABH@B`](-AW0H8VAABHI3...@+r\@
M8V%S=EN9R!P;VEN=5R('1O(YO;BUP;VEN=5R('1Y4-@DJB`](#0[
M(\O('=R:71I;F@=7-I;F@;6%L9F]R;65D('!O:6YT97(-@D-@EY(#T@
M)g...@[(\O('1A:VEN9R!A91R97-S(]F('!AF%M971Eb...@04y$(-H86YG
M:6YG('!O:6YT97(@=F%L=64-@DJ2`](#0[(\O(-H86YG:6YG('9A;'5E
M#0H)#0H):6YT((@/2!C87-T*EN=EY.R`O+R!C87-T:6YG(9R;VT@]I
M;G1EB!T7!E('1O('1Y4...@=AA=!IVXG=!V;v...@t*?0t*#0iv;VED
G(UA:6XH*0T*PT*6EN=!X(#...@-3`[#0h)9F]O*'@I.PT*?0T*
`
end
Re: Programming in D for C++ Programmers mistake
I'm sorry, it must have been some form of nonstandard extension I used! I see now that this fails with gcc.
Programming in D for C++ Programmers mistake
There's a significant issue in the Programming in D for C++ Programmers article (http://www.digitalmars.com/d/2.0/cpptod.html) The Struct Comparison section is quite wrong. In C++, most structs/classes automatically generate comparison operators. Also, these comparison operators are member functions of the struct, not external functions.
