memoize -- AAs don't work for ubyte[4] keys

[Andrei Alexandrescu]

On 1/4/11 12:44 PM, Manfred_Nowak wrote:
> Andrei Alexandrescu wrote:
>
>> Since a few releases ago
>
> upps. sorry for not reading the docs.
>
> -manfred

BTW I think the rgb2cmyk implementation in Higher Order Perl (which I 
copied) is a bit convoluted. A simplified version is:

ubyte[4] rgb2cmyk(ubyte[3] rgb)
{
     immutable m = max(rgb[0], rgb[1], rgb[2]);
     return [ cast(ubyte)(m - rgb[0]), cast(ubyte)(m - rgb[1]),
             cast(ubyte)(m - rgb[2]), ~m ];
}

Two nice typing touches: max does not necessitate a cast because it's 
implemented to return ubyte for ubytes, and ~m also doesn't need a cast 
thanks to value range propagation.

I don't know how to get rid of the remaining casts.


Andrei