Re: Some array casts

[bearophile via Digitalmars-d-learn]

The sizeof values aren't relevant for D array casts. What 
matters are the array contents.


See:

void main() {
int[5] m = cast(int[5])[1, 2, 3, 4, 5];
assert(m == [1, 2, 3, 4, 5]);
pragma(msg, m.sizeof); // 20u
pragma(msg, [1, 2, 3, 4, 5].sizeof); // 8u
}


Bye,
bearophile

Re: Some array casts

[Douglas Peterson via Digitalmars-d-learn]

On Wednesday, 21 January 2015 at 18:08:44 UTC, bearophile wrote:
The sizeof values aren't relevant for D array casts. What 
matters are the array contents.


See:

void main() {
int[5] m = cast(int[5])[1, 2, 3, 4, 5];
assert(m == [1, 2, 3, 4, 5]);
pragma(msg, m.sizeof); // 20u
pragma(msg, [1, 2, 3, 4, 5].sizeof); // 8u
}


Bye,
bearophile


i'm sorry if I've lead you on a wrong way.
My bad.

Re: Some array casts

[bearophile via Digitalmars-d-learn]

Baz:


int[3] m = cast(int[3])[1, 2, 3];
writeln(m.sizeof);
writeln([1, 2, 3].sizeof);


The sizeof values aren't relevant for D array casts. What matters 
are the array contents.


Bye,
bearophile

Re: Some array casts

[Baz via Digitalmars-d-learn]

On Wednesday, 21 January 2015 at 14:31:15 UTC, bearophile wrote:

Currently this is accepted:

int[2] m = cast(int[2])[1, 2];

But Kenji suggests that the cast from int[] to int[2][1] should 
not be accepted. Do you know why?


Reference:
https://issues.dlang.org/show_bug.cgi?id=7514

Bye and thank you,
bearophile


This is because of the .sizeof property, for example:

void main(string[] args)
{
int[3] m = cast(int[3])[1, 2, 3];
writeln(m.sizeof);
writeln([1, 2, 3].sizeof);
}

outputs 12 / 8

Your previous example is corner case, it's 8/8 in both.

Some array casts

[bearophile via Digitalmars-d-learn]

Currently this is accepted:

int[2] m = cast(int[2])[1, 2];

But Kenji suggests that the cast from int[] to int[2][1] should 
not be accepted. Do you know why?


Reference:
https://issues.dlang.org/show_bug.cgi?id=7514

Bye and thank you,
bearophile

Re: Some array casts

[Baz via Digitalmars-d-learn]

On Wednesday, 21 January 2015 at 14:41:48 UTC, Baz wrote:

On Wednesday, 21 January 2015 at 14:31:15 UTC, bearophile wrote:

Currently this is accepted:

int[2] m = cast(int[2])[1, 2];

But Kenji suggests that the cast from int[] to int[2][1] 
should not be accepted. Do you know why?


Reference:
https://issues.dlang.org/show_bug.cgi?id=7514

Bye and thank you,
bearophile


This is because of the .sizeof property, for example:

void main(string[] args)
{
int[3] m = cast(int[3])[1, 2, 3];
writeln(m.sizeof);
writeln([1, 2, 3].sizeof);
}

outputs 12 / 8

Your previous example is corner case, it's 8/8 in both.


with -m32 of course.