• Norbert Nemec (18/18) Apr 24 2004 Hi there,
• J Anderson (4/10) Apr 24 2004 Use a pointer.
• Ivan Senji (4/17) Apr 24 2004 would
• Ivan Senji (9/27) Apr 24 2004 would
• Vathix (6/24) Apr 23 2004 Why not use opIndex? That's what it's there for...
• Norbert Nemec (4/6) Apr 24 2004 a) It is limited to just one index, so it will fail for multidimensional
• Vathix (5/11) Apr 23 2004 I understand. If there were array literals, the index type of opIndex co...

Norbert Nemec <Norbert.Nemec gmx.de> writes:

Hi there,

in C++, it is very common to return references to allow assignment. I would
like to do something similar in D:

--------------------------
class Vector(T) {
        T[] data;
        this(int size) { data.length = size; }
        T& operator(int idx) { return data[idx]; };
};

int
main() {
        Vector!(int) a(3);
        a(2) = 5;
};
--------------------------

However, that T& is not defined in D. What do I do?

Ciao,
Nobbi

J Anderson <REMOVEanderson badmama.com.au> writes:

Norbert Nemec wrote:

Hi there,

in C++, it is very common to return references to allow assignment. I would
like to do something similar in D:

Ciao,
Nobbi
  

Use a pointer.

-- 
-Anderson: http://badmama.com.au/~anderson/

"Ivan Senji" <ivan.senji public.srce.hr> writes:

"J Anderson" <REMOVEanderson badmama.com.au> wrote in message
news:c6dcii$28jj$2 digitaldaemon.com...
 Norbert Nemec wrote:

Hi there,

in C++, it is very common to return references to allow assignment. I


would
like to do something similar in D:

Ciao,
Nobbi

 Use a pointer.

Pointer has to be dereferenced == more complex code!


 --
 -Anderson: http://badmama.com.au/~anderson/

"Ivan Senji" <ivan.senji public.srce.hr> writes:

"Norbert Nemec" <Norbert.Nemec gmx.de> wrote in message
news:c6db59$24t0$1 digitaldaemon.com...
 Hi there,

 in C++, it is very common to return references to allow assignment. I

would
 like to do something similar in D:

I would like to be able to do that too!
This way there are inconsistenties between user defined types (like class)
and non-reference types. This could be a problem in templates and generic
algorithms that should work both for builtin types and for user defined
types
the same way :(

 --------------------------
 class Vector(T) {
         T[] data;
         this(int size) { data.length = size; }
         T& operator(int idx) { return data[idx]; };
 };

 int
 main() {
         Vector!(int) a(3);
         a(2) = 5;
 };
 --------------------------

 However, that T& is not defined in D. What do I do?

 Ciao,
 Nobbi

"Vathix" <vathix dprogramming.com> writes:

From: "Norbert Nemec" <Norbert.Nemec gmx.de>

 Hi there,

 in C++, it is very common to return references to allow assignment. I

would
 like to do something similar in D:

 --------------------------
 class Vector(T) {
         T[] data;
         this(int size) { data.length = size; }
         T& operator(int idx) { return data[idx]; };
 };

 int
 main() {
         Vector!(int) a(3);
         a(2) = 5;
 };
 --------------------------

 However, that T& is not defined in D. What do I do?

 Ciao,
 Nobbi


Why not use opIndex? That's what it's there for...
Type1 opIndex(Type2 index, Type1 value);


--
Christopher E. Miller

Norbert Nemec <Norbert.Nemec gmx.de> writes:

Vathix wrote:
 Why not use opIndex? That's what it's there for...
 Type1 opIndex(Type2 index, Type1 value);

a) It is limited to just one index, so it will fail for multidimensional
arrays

b) it can only be used for assignments but not for inout parameters etc.

"Vathix" <vathix dprogramming.com> writes:

"Norbert Nemec" <Norbert.Nemec gmx.de> wrote in message
news:c6ddf1$2b63$2 digitaldaemon.com...
 Vathix wrote:
 Why not use opIndex? That's what it's there for...
 Type1 opIndex(Type2 index, Type1 value);

 a) It is limited to just one index, so it will fail for multidimensional
 arrays

 b) it can only be used for assignments but not for inout parameters etc.

I understand. If there were array literals, the index type of opIndex could
be int[], and you could specify like:  arr[[3, 4, 5]] = 4;
:)