On Tue, 23 Dec 2014 22:57:07 +0000 "Winter M. via Digitalmars-d-learn" <digitalmars-d-learn@puremagic.com> wrote:
> I've run into a problem while trying to coerce array values from > a variant; specifically, > > char[] a = aVariant.coerce!(char[]); // This works just fine. > > byte[] b = bVariant.coerce!(byte[]); // This causes a static > assertion to fail. > > I'm not really sure why a byte[] would be an unsupported type, > since memory-wise the reference should take up as much space as > for the char[] (as I understand it). > Perhaps I'm missing something, but I'm lost as to why this is the > case. heh. this is due to how `.coerce!` written. it doesn't really checks for arrays, what it checks for is: 1. static if (isNumeric!T || isBoolean!T) 2. static if (is(T : Object)) 3. static if (isSomeString!(T)) see the gotcha? ;-) both types you requested are not numeric, not boolean and not objects. but `char[]` satisfies `isSomeString!`, and `byte[]` doesn't. i don't sure that coercing is designed to work this way, it seems that `isSomeString!` is just a hack for coercing to strings. i.e. with `char[]` variant tries to build some textual representation of it's value, and with `byte[]` variant simply don't know what to do. maybe we should allow coercing to `byte[]` and `ubyte[]` with the defined meaning: "get raw binary representation of variant contents".
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