I almost have to apologize for this question but ..

How does one initialize a static rectangular array (2-d matrix) in D1?

None of the following or other variations that I've tried compile with DMD 1.0.

int[2, 3] matrix = [ 1, 2, 3,  4, 5, 6 ];

int[2, 3] matrix = [[ 1, 2, 3 ], [ 4, 5, 6 ]];

Thanks for all help.

On Thu, Oct 8, 2009 at 8:10 PM, Justin Johansson <no@spam.com> wrote:
> I almost have to apologize for this question but ..
>
> How does one initialize a static rectangular array (2-d matrix) in D1?
>
> None of the following or other variations that I've tried compile with DMD 1.0.
>
> int[2, 3] matrix = [ 1, 2, 3,  4, 5, 6 ];

..that's not how you declare a rectangular array type. It's int[3][2].

int[3][2] matrix = [[1, 2, 3], [4, 5, 6]];

Jarrett Billingsley Wrote:

> On Thu, Oct 8, 2009 at 8:10 PM, Justin Johansson <no@spam.com> wrote:
> > I almost have to apologize for this question but ..
> >
> > How does one initialize a static rectangular array (2-d matrix) in D1?
> >
> > None of the following or other variations that I've tried compile with DMD 1.0.
> >
> > int[2, 3] matrix = [ 1, 2, 3,  4, 5, 6 ];
> 
> ..that's not how you declare a rectangular array type. It's int[3][2].
> 
> int[3][2] matrix = [[1, 2, 3], [4, 5, 6]];

Of course.  Blonde moment.  Worked 18 hrs yesterday & not enough sleep. :-(

Jarrett Billingsley Wrote:

> On Thu, Oct 8, 2009 at 8:10 PM, Justin Johansson <no@spam.com> wrote:
> > I almost have to apologize for this question but ..
> >
> > How does one initialize a static rectangular array (2-d matrix) in D1?
> >
> > None of the following or other variations that I've tried compile with DMD 1.0.
> >
> > int[2, 3] matrix = [ 1, 2, 3,  4, 5, 6 ];
> 
> ..that's not how you declare a rectangular array type. It's int[3][2].
> 
> int[3][2] matrix = [[1, 2, 3], [4, 5, 6]];

Thanks Jarrett.

Am I having a blonde day?

   int[2,3] m = [ 1, 2, 3 ];
   writefln( "m=%s, .sizeof=%d", m, m.sizeof);

Compiles and prints:

m=[1,2,3], .sizeof=12

So what does that declaration, int[2,3], mean?

Think this is what threw me initially.

Thanks, Justin

Justin Johansson wrote:
> Jarrett Billingsley Wrote:
> 
>> On Thu, Oct 8, 2009 at 8:10 PM, Justin Johansson <no@spam.com> wrote:
>>> I almost have to apologize for this question but ..
>>>
>>> How does one initialize a static rectangular array (2-d matrix) in D1?
>>>
>>> None of the following or other variations that I've tried compile with DMD 1.0.
>>>
>>> int[2, 3] matrix = [ 1, 2, 3,  4, 5, 6 ];
>> ..that's not how you declare a rectangular array type. It's int[3][2].
>>
>> int[3][2] matrix = [[1, 2, 3], [4, 5, 6]];
> 
> Thanks Jarrett.
> 
> Am I having a blonde day?
> 
>    int[2,3] m = [ 1, 2, 3 ];    writefln( "m=%s, .sizeof=%d", m, m.sizeof);
> 
> Compiles and prints:
> 
> m=[1,2,3], .sizeof=12
> 
> So what does that declaration, int[2,3], mean?
> 
> Think this is what threw me initially.
> 
> Thanks, Justin

2,3 is a comma expression. Evaluate everything, and return the rightmost value.

Justin Johansson wrote:
> Jarrett Billingsley Wrote:
> 
>> On Thu, Oct 8, 2009 at 8:10 PM, Justin Johansson <no@spam.com> wrote:
> 
> Thanks Jarrett.
> 
> Am I having a blonde day?
> 
>    int[2,3] m = [ 1, 2, 3 ];
>    writefln( "m=%s, .sizeof=%d", m, m.sizeof);
> 
> Compiles and prints:
> 
> m=[1,2,3], .sizeof=12
> 
> So what does that declaration, int[2,3], mean?
> 
> Think this is what threw me initially.
> 
> Thanks, Justin
> 

It probably means DMD isn't doing enough validation checking.

Comma expression, hence typeof(m) is int[3], m.sizeof is 3 * int.sizeof

On Thu, Oct 8, 2009 at 10:05 PM, Christopher Wright <dhasenan@gmail.com> wrote:
> Justin Johansson wrote:
>>
>> Jarrett Billingsley Wrote:
>>
>>> On Thu, Oct 8, 2009 at 8:10 PM, Justin Johansson <no@spam.com> wrote:
>>>>
>>>> I almost have to apologize for this question but ..
>>>>
>>>> How does one initialize a static rectangular array (2-d matrix) in D1?
>>>>
>>>> None of the following or other variations that I've tried compile with DMD 1.0.
>>>>
>>>> int[2, 3] matrix = [ 1, 2, 3,  4, 5, 6 ];
>>>
>>> ..that's not how you declare a rectangular array type. It's int[3][2].
>>>
>>> int[3][2] matrix = [[1, 2, 3], [4, 5, 6]];
>>
>> Thanks Jarrett.
>>
>> Am I having a blonde day?
>>
>>   int[2,3] m = [ 1, 2, 3 ];   writefln( "m=%s, .sizeof=%d", m, m.sizeof);
>>
>> Compiles and prints:
>>
>> m=[1,2,3], .sizeof=12
>>
>> So what does that declaration, int[2,3], mean?
>>
>> Think this is what threw me initially.
>>
>> Thanks, Justin
>
> 2,3 is a comma expression. Evaluate everything, and return the rightmost value.
>

Bahahaha, oh comma exps.

Jarrett Billingsley Wrote:

> Bahahaha, oh comma exps.

Their usage will need to be quite regulated in D (using them for smarter purposes is a cute idea, but it may impair C compatibility).

Bye,
bearophile