I have the following C code, how can I do the same in D.

Info **info;
info = new Info*[hl + 2];

int r;
for(r = 0; r < hl; r++)
{
	info[r] = new Info[vl + 2];
}
info[r] = NULL;

anon

On Wed, 21 Jan 2015 23:44:49 +0000
anon via Digitalmars-d-learn <digitalmars-d-learn@puremagic.com> wrote:

> I have the following C code, how can I do the same in D.
> 
> Info **info;
> info = new Info*[hl + 2];
> 
> int r;
> for(r = 0; r < hl; r++)
> {
> 	info[r] = new Info[vl + 2];
> }
> info[r] = NULL;
> 
> anon
this is not C.

On Wednesday, 21 January 2015 at 23:47:46 UTC, ketmar via Digitalmars-d-learn wrote:
> On Wed, 21 Jan 2015 23:44:49 +0000
> anon via Digitalmars-d-learn <digitalmars-d-learn@puremagic.com> wrote:
>
>> I have the following C code, how can I do the same in D.
>> 
>> Info **info;
>> info = new Info*[hl + 2];
>> 
>> int r;
>> for(r = 0; r < hl; r++)
>> {
>> 	info[r] = new Info[vl + 2];
>> }
>> info[r] = NULL;
>> 
>> anon
> this is not C.

Your right its c++

On Wed, 21 Jan 2015 23:50:59 +0000
anon via Digitalmars-d-learn <digitalmars-d-learn@puremagic.com> wrote:

> On Wednesday, 21 January 2015 at 23:47:46 UTC, ketmar via Digitalmars-d-learn wrote:
> > On Wed, 21 Jan 2015 23:44:49 +0000
> > anon via Digitalmars-d-learn
> > <digitalmars-d-learn@puremagic.com> wrote:
> >
> >> I have the following C code, how can I do the same in D.
> >> 
> >> Info **info;
> >> info = new Info*[hl + 2];
> >> 
> >> int r;
> >> for(r = 0; r < hl; r++)
> >> {
> >> 	info[r] = new Info[vl + 2];
> >> }
> >> info[r] = NULL;
> >> 
> >> anon
> > this is not C.
> 
> Your right its c++
so the answer to your question is very easy: just type in any gibberish. as C cannot compile C++ code, the final result is to get the code that cannot be compiled. any gibberish will do.

On Wednesday, 21 January 2015 at 23:59:34 UTC, ketmar via Digitalmars-d-learn wrote:
> On Wed, 21 Jan 2015 23:50:59 +0000
> anon via Digitalmars-d-learn <digitalmars-d-learn@puremagic.com> wrote:
>
>> On Wednesday, 21 January 2015 at 23:47:46 UTC, ketmar via Digitalmars-d-learn wrote:
>> > On Wed, 21 Jan 2015 23:44:49 +0000
>> > anon via Digitalmars-d-learn <digitalmars-d-learn@puremagic.com> wrote:
>> >
>> >> I have the following C code, how can I do the same in D.
>> >> 
>> >> Info **info;
>> >> info = new Info*[hl + 2];
>> >> 
>> >> int r;
>> >> for(r = 0; r < hl; r++)
>> >> {
>> >> 	info[r] = new Info[vl + 2];
>> >> }
>> >> info[r] = NULL;
>> >> 
>> >> anon
>> > this is not C.
>> 
>> Your right its c++
> so the answer to your question is very easy: just type in any
> gibberish. as C cannot compile C++ code, the final result is to get the
> code that cannot be compiled. any gibberish will do.

Great answer.

Anyway the code isn't mine I just wanted to know how to handle what the author wrote.

I got it working with.

auto info = new Info[][](hl, vl);

and changing the logic so as not check for the NULL.

No need on being picky it was just a question.

anon

anon:

> I have the following C code, how can I do the same in D.
>
> Info **info;
> info = new Info*[hl + 2];
>
> int r;
> for(r = 0; r < hl; r++)
> {
> 	info[r] = new Info[vl + 2];
> }
> info[r] = NULL;

I suggest you to ignore ketmar, he's not helping :-)

Is your code initializing info[r+1]?

This is roughly a D translation (untested):


void main() @safe {
    import std.stdio;

    enum uint hl = 5;
    enum uint vl = 7;
    static struct Info {}

    auto info = new Info[][](hl + 2);

    foreach (ref r; info[0 .. hl])
        r = new Info[vl + 2];

    writefln("[\n%(%s,\n%)\n]", info);
}


Output:

[
[Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info()],
[Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info()],
[Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info()],
[Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info()],
[Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info()],
[],
[]
]


Is this what you look for?

Bye,
bearophile

On Wednesday, 21 January 2015 at 23:44:52 UTC, anon wrote:
> I have the following C code, how can I do the same in D.
>
> Info **info;
> info = new Info*[hl + 2];
>
> int r;
> for(r = 0; r < hl; r++)
> {
> 	info[r] = new Info[vl + 2];
> }
> info[r] = NULL;
>
> anon

The super-literal translation:
    Info** info;
    info = new Info*[hl + 2].ptr;
    int r;
    for(r = 0; r < hl; r++)
    {
        info[r] = new Info[vl + 2].ptr;
    }
    info[r] = null;

A little more D-ish:
    Info[][] info = new Info[][hl + 2];
    foreach(r; 0 .. hl)
    {
        info[r] = new Info[vl + 2];
    }
    assert(info[hl].length == 0); /* Relying on default initialization. */

D to the ultimate max:
    import std.algorithm;
    import std.range;
    auto info = iota(hl)
        .map!(i => new Info[vl + 2])
        .chain(only(Info[].init, Info[].init))
        .array;
    static assert(is(typeof(info) == Info[][]));
    assert(info.length == hl + 2);
    assert(info[hl].empty);

And if those +2 are for sentinel values, D doesn't need them because D arrays know their length. And it all comes down to:
    auto info = new Info[][](hl, vl);

anon:

> I got it working with.
>
> auto info = new Info[][](hl, vl);
>
> and changing the logic so as not check for the NULL.

That's probably a better and simpler translation. I have tried to translate your original code too much literally.

Bye,
bearophile

On Thursday, 22 January 2015 at 00:16:23 UTC, bearophile wrote:
> anon:
>
>> I have the following C code, how can I do the same in D.
>>
>> Info **info;
>> info = new Info*[hl + 2];
>>
>> int r;
>> for(r = 0; r < hl; r++)
>> {
>> 	info[r] = new Info[vl + 2];
>> }
>> info[r] = NULL;
>
> I suggest you to ignore ketmar, he's not helping :-)
>
> Is your code initializing info[r+1]?
>
> This is roughly a D translation (untested):
>
>
> void main() @safe {
>     import std.stdio;
>
>     enum uint hl = 5;
>     enum uint vl = 7;
>     static struct Info {}
>
>     auto info = new Info[][](hl + 2);
>
>     foreach (ref r; info[0 .. hl])
>         r = new Info[vl + 2];
>
>     writefln("[\n%(%s,\n%)\n]", info);
> }
>
>
> Output:
>
> [
> [Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info()],
> [Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info()],
> [Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info()],
> [Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info()],
> [Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info(), Info()],
> [],
> []
> ]
>
>
> Is this what you look for?
>
> Bye,
> bearophile

Hi Bearophile,

It looks like what I need.

Thanks,
anon

anon:

> It looks like what I need.

But what's the purpose of the last two empty arrays?

Bye,
bearophile