I'm running GDC on mac OSX. The mac tags events with a four character code which
is converted to a
UInt32 along the lines of:

(s[0] << 24) || (s[1] << 16) || (s[2] << 8) || (s[3])

where s[n] is the ascii charater number.

I need to declare:

const OSType	kEventClassCommand            = FOUR_CHAR_CODE("cmds");

Browsing the documentation seems to indicate I need a template but I can't seem
to work out how. Can
anybody help?

Thanks

Gareth Baker
g.j.baker at dl.ac.uk

Gareth Baker wrote:

> I need to declare:
> 
> const OSType	kEventClassCommand            = FOUR_CHAR_CODE("cmds");
> 
> Browsing the documentation seems to indicate I need a template but I can't seem
> to work out how. Can anybody help?

Not what you want (since it isn't automatic), but I used:

# echo "cmds" | hexdump
0000000 636d 6473 0a00
0000005

Which means that the value of your constant is 0x636d6473

--anders

Gareth Baker wrote:
> I'm running GDC on mac OSX. The mac tags events with a four character code which
> is converted to a UInt32 along the lines of:
> 
> (s[0] << 24) || (s[1] << 16) || (s[2] << 8) || (s[3])
> 
> where s[n] is the ascii charater number.
> 
> I need to declare:
> 
> const OSType	kEventClassCommand            = FOUR_CHAR_CODE("cmds");


template FourCharCode(char[] s) {
  static assert(s.length == 4);
  const uint FourCharCode = (s[0]<<24)|(s[1]<<16)|(s[2]<<8)|(s[3]);
}

int main() {
  writefln("%x",FourCharCode!("cmds"));
  return 0;
}

/Oskar

Gareth Baker schrieb am 2006-02-23:
> I'm running GDC on mac OSX. The mac tags events with a four character code which
> is converted to a
> UInt32 along the lines of:
>
> (s[0] << 24) || (s[1] << 16) || (s[2] << 8) || (s[3])
>
> where s[n] is the ascii charater number.
>
> I need to declare:
>
> const OSType    kEventClassCommand            = FOUR_CHAR_CODE("cmds");
>
> Browsing the documentation seems to indicate I need a template but I can't seem
> to work out how. Can
> anybody help?


| template FOUR_CHAR_CODE(char[] cmd){
|     static if(cmd.length != 4){
|         pragma(msg, "require 4 chars");
|         static assert(0);
|     }else{
|         const uint FOUR_CHAR_CODE = (cmd[0] << 24) | (cmd[1] << 16) | (cmd[2] << 8) | cmd[3];
|     }
| }

...

| const OSType    kEventClassCommand = FOUR_CHAR_CODE!("cmds");

Thomas

Thanks for the answers. I'll give them a go tonight.

Gareth Baker
g.j.baker at dl.ac.uk

Thomas Kuehne wrote:

> | template FOUR_CHAR_CODE(char[] cmd){
> |     static if(cmd.length != 4){
> |         pragma(msg, "require 4 chars");
> |         static assert(0);
> |     }else{
> |         const uint FOUR_CHAR_CODE = (cmd[0] << 24) | (cmd[1] << 16) | (cmd[2] << 8) | cmd[3];
> |     }
> | }

Seems to do the trick. (returns 0x636d6473)

--anders