0ffh schrieb:
> BLS wrote:
>> Actually coding C++ code in D  means : rewrite it and make it D-ish, instead of translate it.
>> This is , simply said shit; and I guess you folks know it.
> 
> Nope, actually, I don't. If you're so in love with C++, why bother with D?
> 
> Regards, Frank
NOOOOOoooo, clarification ;-), I don't like C++, BUT I need to translate some Cpp libs into D. And sometimes it is difficult to do this job 'cause D 1.x actually lacks some of C++ features. (but D 2 comes with struct inheritance., opImplicitCastX, DTL, ....)
Bjoern

beside, C++ is No 2 on my personal programming language SL

BLS wrote:
> 0ffh schrieb:
>> If you're so in love with C++, why bother with D?
> NOOOOOoooo, clarification ;-), I don't like C++, BUT I need to translate
> some Cpp libs into D. And sometimes it is difficult to do this job [...]

I suppose life just isn't fair. =)

> beside, C++ is No 2 on my personal programming language SL

What is an SL?

Earlier, BLS wrote:
> &references ... The Rationales do not say a anything about it The D "compared to C" just says ... We don't have it.

Yup, and good riddance I say!
IMHO even the out/ref keyword is a mistake!
(It's also the only mistake of it's kind in Pascal, btw.)

> Struct inheritance Why we need an *alias here instead of just writing structA : structB;

Maybe you have a point here. I suppose mixins can't be used, as there
would probably be a problem overriding.

> C++ op overloading; D is not competitive.

Hmmmm.... I can't recall any major issues here.

Regards, Frank

0ffh schrieb:
> BLS wrote:
>> 0ffh schrieb:
>>> If you're so in love with C++, why bother with D?
>> NOOOOOoooo, clarification ;-), I don't like C++, BUT I need to translate
>> some Cpp libs into D. And sometimes it is difficult to do this job [...]
> 
> I suppose life just isn't fair. =)
> 
>> beside, C++ is No 2 on my personal programming language SL
> 
> What is an SL?
> 

I am pretty sure Gerhard Schroeder still has a top ten placement on George W. Bush's S-List, HTH :)

> Earlier, BLS wrote:
>> &references ... The Rationales do not say a anything about it The D "compared to C" just says ... We don't have it.
> 
> Yup, and good riddance I say!
> IMHO even the out/ref keyword is a mistake!
> (It's also the only mistake of it's kind in Pascal, btw.)
> 

I do not agree, but this is not the point. The problem is that C++ folks seems to love this feature, and I have to translate it into D (somehow).

>> Struct inheritance Why we need an *alias here instead of just writing structA : structB;
> 
> Maybe you have a point here. I suppose mixins can't be used, as there
> would probably be a problem overriding.
> 
>> C++ op overloading; D is not competitive.
> 
> Hmmmm.... I can't recall any major issues here.
> 

For example :
// Allready translated C++ stuff
class CFont
{
public:
  HFONT m_hFont;

  this(HFONT hFont = null)
  {
    m_hFont = hFont;
  }
  ~this()
  {
    if(m_hFont !is null && !DeleteObject(m_hFont))
    m_hFont = null;
  }

// TODO How to translate this C++ construct  into D

    operator HFONT() {return m_hFont;}

// That's the problem.
But as allready said/ D 2 opImplicitCast may solve the problem.

> Regards, Frank
Thanks Bjoern

BLS wrote:
> 0ffh schrieb:
>> Earlier, BLS wrote:
>>> &references ... The Rationales do not say a anything about it The D "compared to C" just says ... We don't have it.
>> Yup, and good riddance I say!
>> IMHO even the out/ref keyword is a mistake!
>> (It's also the only mistake of it's kind in Pascal, btw.)
> I do not agree, but this is not the point. The problem is that C++ folks seems to love this feature, and I have to translate it into D (somehow).

With the help of explicit pointers and dereferencing, I can see no trouble
except you'll need a lot of stars... :)

Regards, Frank

ps. btw. plain C doesn't have &refs either

0ffh schrieb:

> With the help of explicit pointers and dereferencing, I can see no trouble
> except you'll need a lot of stars... :)
> 
> Regards, Frank
> 
> ps. btw. plain C doesn't have &refs either

Would be nice if you are willing to offer an example.
It could also be used as example on :
http://www.prowiki.org/wiki4d/wiki.cgi?PortingFromCxx
thanks in advance, Bjoern

BLS wrote:
> 0ffh schrieb:
> 
>> With the help of explicit pointers and dereferencing, I can see no trouble
>> except you'll need a lot of stars... :)
>>
>> Regards, Frank
>>
>> ps. btw. plain C doesn't have &refs either
> 
> Would be nice if you are willing to offer an example.
> It could also be used as example on :
> http://www.prowiki.org/wiki4d/wiki.cgi?PortingFromCxx
> thanks in advance, Bjoern

He just means have the function return Foo* instead of Foo&.  And then use (*foo) everwhere instead of plain foo on calling side.  That's pretty much the only reasonable solution I can see.

--bb

Bill Baxter schrieb:
> BLS wrote:
>> 0ffh schrieb:
>>
>>> With the help of explicit pointers and dereferencing, I can see no trouble
>>> except you'll need a lot of stars... :)
>>>
>>> Regards, Frank
>>>
>>> ps. btw. plain C doesn't have &refs either
>>
>> Would be nice if you are willing to offer an example.
>> It could also be used as example on :
>> http://www.prowiki.org/wiki4d/wiki.cgi?PortingFromCxx
>> thanks in advance, Bjoern
> 
> He just means have the function return Foo* instead of Foo&.  And then use (*foo) everwhere instead of plain foo on calling side.  That's pretty much the only reasonable solution I can see.
> 
> --bb
Thanks for clarification Bill. Wonder why Frank wrote : "except you'll need a lot of * " ?
Bjoern

BLS wrote:
> Bill Baxter schrieb:
>> BLS wrote:
>>> 0ffh schrieb:
>>>
>>>> With the help of explicit pointers and dereferencing, I can see no trouble
>>>> except you'll need a lot of stars... :)
>>>>
>>>> Regards, Frank
>>>>
>>>> ps. btw. plain C doesn't have &refs either
>>>
>>> Would be nice if you are willing to offer an example.
>>> It could also be used as example on :
>>> http://www.prowiki.org/wiki4d/wiki.cgi?PortingFromCxx
>>> thanks in advance, Bjoern
>>
>> He just means have the function return Foo* instead of Foo&.  And then use (*foo) everwhere instead of plain foo on calling side.  That's pretty much the only reasonable solution I can see.
>>
>> --bb
> Thanks for clarification Bill. Wonder why Frank wrote : "except you'll need a lot of * " ?
> Bjoern
> 

I assumed he meant something like:

-- C++ --
void foo(int &i)
{
  ..lots of uses of 'i' eg "i = 5"..
}

-- D --
void foo(int *i)
{
  ..lots of uses of '*i' eg "*i = 5"..
}

each usage of a converted ref parameter will require a *.

The other problem here however is the call site:

-- C++ --
int i;
foo(i);

-- D --
int i;
foo(&i);

Regan

BLS wrote:
> Would be nice if you are willing to offer an example.
> It could also be used as example on :
> http://www.prowiki.org/wiki4d/wiki.cgi?PortingFromCxx
> thanks in advance, Bjoern

Okay, I am more a C type of person not C++, so I hope
I do not write anything wrong now... :)

I have a C++ function getting an int &a:

---<snip>---

void addTo(int &a,int b)
{
  a+=b;
}

void main()
{
  int a=5;
  addTo(a,3);
  printf("a=%i\n",a); // prints "a=8\n"
}

---<snap>---

IIRC this is really just syntactic sugar for passing
a pointer that is automatically dereferenced.
In C I replace the &a with an *a and dereference:

---<snip>---

void addTo(int *a,int b) // &a -> *a
{
  (*a)+=b; // a -> (*a)
}

void main()
{
  int a=5;
  addTo(&a,3); // a -> &a
  printf("a=%i\n",a); // prints "a=8\n"
}

---<snap>---

This has the added advantage, that at the point where the
function is called, I can see that a pointer is passed,
while in C++ I can't. That's why C++ coders so often write
(const T &ref) to avoid accidential side effects which
would be hard to find just looking at the function call.

This might work in D, although I have never tried it:

---<snip>---

void addTo(ref int a,int b)
{
  a+=b;
}

void main()
{
  int a=5;
  addTo(a,3);
  printf("a=%i\n",a); // prints "a=8\n"
}

---<snap>---

Regards, Frank

Regan Heath schrieb:
> BLS wrote:
>> Bill Baxter schrieb:
>>> BLS wrote:
>>>> 0ffh schrieb:
>>>>
>>>>> With the help of explicit pointers and dereferencing, I can see no trouble
>>>>> except you'll need a lot of stars... :)
>>>>>
>>>>> Regards, Frank
>>>>>
>>>>> ps. btw. plain C doesn't have &refs either
>>>>
>>>> Would be nice if you are willing to offer an example.
>>>> It could also be used as example on :
>>>> http://www.prowiki.org/wiki4d/wiki.cgi?PortingFromCxx
>>>> thanks in advance, Bjoern
>>>
>>> He just means have the function return Foo* instead of Foo&.  And then use (*foo) everwhere instead of plain foo on calling side.  That's pretty much the only reasonable solution I can see.
>>>
>>> --bb
>> Thanks for clarification Bill. Wonder why Frank wrote : "except you'll need a lot of * " ?
>> Bjoern
>>
> 
> I assumed he meant something like:
> 
> -- C++ --
> void foo(int &i)
> {
>   ..lots of uses of 'i' eg "i = 5"..
> }
> 
> -- D --
> void foo(int *i)
> {
>   ..lots of uses of '*i' eg "*i = 5"..
> }
> 

I think :
void foo(ref int i){}
will do the Job in D
( But function parameters are not part of the problem )
Thanks, Bjoern

> each usage of a converted ref parameter will require a *.
> 
> The other problem here however is the call site:
> 
> -- C++ --
> int i;
> foo(i);
> 
> -- D --
> int i;
> foo(&i);
> 
> Regan