Re: Is there any writeln like functions without GC?
On Thursday, 31 October 2019 at 03:56:56 UTC, lili wrote: Hi: why writeln need GC? See also Mir's @nogc formatting module https://github.com/libmir/mir-runtime/blob/master/source/mir/format.d
Re: Is there any writeln like functions without GC?
On Thursday, 31 October 2019 at 16:03:22 UTC, bachmeier wrote: On Thursday, 31 October 2019 at 15:11:42 UTC, Ferhat Kurtulmuş wrote: It would be nice if one reimplement writeln of Phobos by bypassing gc and use a custom nogc exception as described here*? Of course I can imagine that it would be a breaking change in the language and requires so much work for it to be compatible with other std modules/language features. *: https://www.auburnsounds.com/blog/2016-11-10_Running-D-without-its-runtime.html I can't imagine any possibility we'll ever see a breaking change to writeln. It would have to be an addition to Phobos. Yep or Phobos 2 which is more realistic at this point.
Re: Is there any writeln like functions without GC?
On Thursday, October 31, 2019 9:11:42 AM MDT Ferhat Kurtulmuş via Digitalmars-d-learn wrote: > On Thursday, 31 October 2019 at 13:46:07 UTC, Adam D. Ruppe wrote: > > On Thursday, 31 October 2019 at 03:56:56 UTC, lili wrote: > >> Hi: > >>why writeln need GC? > > > > It almost never does, it just keeps the option open in case > > > > * it needs to throw an exception (like if stdout is closed) > > > > * you pass it a custom type with toString that uses GC > > > > @nogc is just super strict and doesn't even allow for rare > > cases. > > It would be nice if one reimplement writeln of Phobos by > bypassing gc and use a custom nogc exception as described here*? > Of course I can imagine that it would be a breaking change in the > language and requires so much work for it to be compatible with > other std modules/language features. > > *: > https://www.auburnsounds.com/blog/2016-11-10_Running-D-without-its-runtime > .html You can always just use printf. - Jonathan M Davis
Re: Unable to pass a D function member to a C callback
On Saturday, 2 November 2019 at 20:42:29 UTC, Luh wrote: Yup that's it ! Many thanks ! One word of warning: ensure the C library does not have the only reference to your Game class instance, or the garbage collector might deallocate it since it does not scan threads created by C libraries. See: https://dlang.org/spec/garbage.html#gc_foreign_obj
Re: Unable to pass a D function member to a C callback
On Saturday, 2 November 2019 at 19:55:58 UTC, Dennis wrote: On Saturday, 2 November 2019 at 19:42:54 UTC, Luh wrote: So I think I just can't. :( Is that `void* c` in the callback a context pointer by any chance? That's a common thing in C callbacks precisely for purposes like this. You can cast your class to a void* when you register the callback and in the callback function cast it back to a class and call process on that. I don't know what C library you're working with so can't give you specifics. Yup that's it ! Many thanks !
Which is the active fork in DFL gui library ?
Hi all, I just found that DFL gui library very interesting. But after some searching, i can see that DFL is inactive and there is few other forks for it. So this is my question - Which fork is good for a gui development in windows platform. BTW, i just tested the gtkD and successfully compiled a hello app. How do i avoid the console window when compiling gtkD app ? Thanks in advance.
Re: Unable to pass a D function member to a C callback
On Saturday, 2 November 2019 at 19:42:54 UTC, Luh wrote: So I think I just can't. :( Is that `void* c` in the callback a context pointer by any chance? That's a common thing in C callbacks precisely for purposes like this. You can cast your class to a void* when you register the callback and in the callback function cast it back to a class and call process on that. I don't know what C library you're working with so can't give you specifics.
Re: Unable to pass a D function member to a C callback
On Saturday, 2 November 2019 at 18:31:28 UTC, Stefan Koch wrote:
On Saturday, 2 November 2019 at 17:49:09 UTC, Luh wrote:
Hello,
When trying to pass a D function to the C callback, the
compiler says:
'Error: cannot implicitly convert expression &this.onProcessCb
of type extern (C) bool delegate(const(short*) a, ulong b,
void* c) to extern (C) bool function(const(short*), ulong,
void*'
because my function is member of a class (compiles when the
function is out of the class).
Is there any way to say to solve this ?
The wiki isn't very clear about the C callbacks:
https://dlang.org/spec/interfaceToC.html#callbacks
C code:
typedef bool (*onProcessCallback)(const short*, size_t, void*);
D Code:
-
class Game
{
onProcessCallback m_onProcessCb;
this()
{
m_onProcessCb = &onProcessCb; // Error here
}
void onProcess()
{
// ...
}
extern(C) bool onProcessCb(const short* a, size_t b, void* c)
{
onProcess();
return true;
}
}
private extern(C)
{
// Should call onProcess() when executed by the C lib
alias onProcessCallback = bool function(const short*, size_t,
void*);
}
-
you are missing a static in your member function's signature.
The callback is not providing a this pointer.
My problem is, that the onProcess function should not be static
because it uses a variable inside the class.
like:
-
class Game
{
private short[] m_a;
void onProcess(short[] a)
{
m_a ~= a;
// ...
}
extern(C) bool onProcessCb(const short* a, size_t b, void* c)
{
onProcess();
return true;
}
}
-
So I think I just can't. :(
Re: Unable to pass a D function member to a C callback
On Saturday, 2 November 2019 at 17:49:09 UTC, Luh wrote:
Hello,
When trying to pass a D function to the C callback, the
compiler says:
'Error: cannot implicitly convert expression &this.onProcessCb
of type extern (C) bool delegate(const(short*) a, ulong b,
void* c) to extern (C) bool function(const(short*), ulong,
void*'
because my function is member of a class (compiles when the
function is out of the class).
Is there any way to say to solve this ?
The wiki isn't very clear about the C callbacks:
https://dlang.org/spec/interfaceToC.html#callbacks
C code:
typedef bool (*onProcessCallback)(const short*, size_t, void*);
D Code:
-
class Game
{
onProcessCallback m_onProcessCb;
this()
{
m_onProcessCb = &onProcessCb; // Error here
}
void onProcess()
{
// ...
}
extern(C) bool onProcessCb(const short* a, size_t b, void* c)
{
onProcess();
return true;
}
}
private extern(C)
{
// Should call onProcess() when executed by the C lib
alias onProcessCallback = bool function(const short*, size_t,
void*);
}
-
This is because onProcessCb is a member of an object. Therefore,
it carries also the information about the context, which includes
e.g. all members of the class.
Due to this onProcessCb is a delegate, which is something
different from a function, cf.
https://dlang.org/spec/function.html#closures
So, there is a type mismatch.
Re: Unable to pass a D function member to a C callback
On Saturday, 2 November 2019 at 17:49:09 UTC, Luh wrote:
Hello,
When trying to pass a D function to the C callback, the
compiler says:
'Error: cannot implicitly convert expression &this.onProcessCb
of type extern (C) bool delegate(const(short*) a, ulong b,
void* c) to extern (C) bool function(const(short*), ulong,
void*'
because my function is member of a class (compiles when the
function is out of the class).
Is there any way to say to solve this ?
The wiki isn't very clear about the C callbacks:
https://dlang.org/spec/interfaceToC.html#callbacks
C code:
typedef bool (*onProcessCallback)(const short*, size_t, void*);
D Code:
-
class Game
{
onProcessCallback m_onProcessCb;
this()
{
m_onProcessCb = &onProcessCb; // Error here
}
void onProcess()
{
// ...
}
extern(C) bool onProcessCb(const short* a, size_t b, void* c)
{
onProcess();
return true;
}
}
private extern(C)
{
// Should call onProcess() when executed by the C lib
alias onProcessCallback = bool function(const short*, size_t,
void*);
}
-
you are missing a static in your member function's signature.
The callback is not providing a this pointer.
Unable to pass a D function member to a C callback
Hello,
When trying to pass a D function to the C callback, the compiler
says:
'Error: cannot implicitly convert expression &this.onProcessCb of
type extern (C) bool delegate(const(short*) a, ulong b, void* c)
to extern (C) bool function(const(short*), ulong, void*'
because my function is member of a class (compiles when the
function is out of the class).
Is there any way to say to solve this ?
The wiki isn't very clear about the C callbacks:
https://dlang.org/spec/interfaceToC.html#callbacks
C code:
typedef bool (*onProcessCallback)(const short*, size_t, void*);
D Code:
-
class Game
{
onProcessCallback m_onProcessCb;
this()
{
m_onProcessCb = &onProcessCb; // Error here
}
void onProcess()
{
// ...
}
extern(C) bool onProcessCb(const short* a, size_t b, void* c)
{
onProcess();
return true;
}
}
private extern(C)
{
// Should call onProcess() when executed by the C lib
alias onProcessCallback = bool function(const short*, size_t,
void*);
}
-
Re: Execute certain Tests?
On Saturday, 2 November 2019 at 17:27:14 UTC, Martin Brezel wrote: Is there a trick to execute only the test, defined in one file? Or the Tests of a certain Module? Or in general: How to avoid to execute all the tests, when running "dub test"? It doesn't has to be dub, though. dmd -unittest -run -main module.d
Re: Execute certain Tests?
On Saturday, 2 November 2019 at 17:27:14 UTC, Martin Brezel wrote: Is there a trick to execute only the test, defined in one file? Or the Tests of a certain Module? Or in general: How to avoid to execute all the tests, when running "dub test"? It doesn't has to be dub, though. Not by default, if you know the language well then you can use UDAs to write a fancy test runner in ten minutes, if not then use Attila's unit-threaded (or similar) Max
Execute certain Tests?
Is there a trick to execute only the test, defined in one file? Or the Tests of a certain Module? Or in general: How to avoid to execute all the tests, when running "dub test"? It doesn't has to be dub, though.
