Hi everyone,

I'm just starting with D and i need a way to declare a byte array
something like:

byte[] arr = [ 0x00, 0xA4, 0x04];

This throws a int[] to byte[] cast error

Tried also these ones

byte[] arr = "\x00\xA4\x04";
byte[] arr = [ '\x00', '\xA4', '\x04'];
byte[] arr = [ u'\x00', u'\xA4', u'\x04'];
byte[] arr = [ b'\x00', b'\xA4', b'\x04'];

I also tried
byte[] arr = [cast(byte) 0x00, cast(byte)0xA4, cast(byte) 0x04];
and this at least compiles

I read the online book and nowhere there is a byte literal mentioned.

Is there another way besides casting to byte?

Thanks in Advance.

Anibal:

> byte[] arr = [ 0x00, 0xA4, 0x04];
>
> This throws a int[] to byte[] cast error

You want ubytes (unsigned bytes) because 0x04 is 164 that is bigger than byte.max.

So use:

ubyte[] arr = [ 0x00, 0xA4, 0x04];


> I also tried
> byte[] arr = [cast(byte) 0x00, cast(byte)0xA4, cast(byte) 0x04];
> and this at least compiles

Generally in D try to mimize as much as possible the usage of cast().

Bye,
bearophile

> You want ubytes (unsigned bytes) because 0x04 is 164 that is bigger than byte.max.

I'd like bytes to be named sbyte and ubyte in D, but Walter has refused this.

Bye,
bearophile

On Thursday, 9 October 2014 at 15:41:48 UTC, bearophile wrote:
>> You want ubytes (unsigned bytes) because 0x04 is 164 that is bigger than byte.max.
>
> I'd like bytes to be named sbyte and ubyte in D, but Walter has refused this.
>
> Bye,
> bearophile


Got it to work, thanks a lot!

On Thu, 09 Oct 2014 15:26:52 +0000
Anibal via Digitalmars-d-learn <digitalmars-d-learn@puremagic.com>
wrote:

additionally to all bearophile said, there is another interesting thing in D: special string literals for hex data.

  immutable ubyte[] n = cast(typeof(n))x"deadf00d";

or even:

  immutable ubyte[] n = cast(typeof(n))x"de ad f 0 0 d";

spaces doesn't matter, only digits do.

ketmar:

> additionally to all bearophile said, there is another interesting thing in D: special string literals for hex data.
>
>   immutable ubyte[] n = cast(typeof(n))x"deadf00d";
>
> or even:
>
>   immutable ubyte[] n = cast(typeof(n))x"de ad f 0 0 d";
>
> spaces doesn't matter, only digits do.

The problem is that cast. No one wants a string, most people want a ubyte[].

See:
https://issues.dlang.org/show_bug.cgi?id=3850
https://issues.dlang.org/show_bug.cgi?id=5909
https://issues.dlang.org/show_bug.cgi?id=10454

Bye,
bearophile

On Thu, 09 Oct 2014 20:08:11 +0000
bearophile via Digitalmars-d-learn <digitalmars-d-learn@puremagic.com>
wrote:

> The problem is that cast. No one wants a string, most people want a ubyte[].
This doesn't make the cut. it's handy, people wants it, it will break almost nothing... no way.