"if" is not evaluated for fields of Class.tupleof

[Stanislav Blinov via Digitalmars-d-learn]

On Tuesday, 23 May 2017 at 06:42:55 UTC, Timoses wrote:
> The easiest way is probably casting:
>
> ```
> import std.traits;
> import std.bitmanip;
>
> class Test {
>     byte[4] marray;
>     byte mbyte;
> }
>
> void main() {
>     auto value = [0x12, 0x23, 0x34, 0x45, 0x56];
>     auto test = cast(Test*) value.ptr;
> }
> ```

Don't cast arbitrary types to classes, you're going to stumble 
upon very nasty surprises :) I guess you meant struct?

Classes in D are quite fat, and don't start with data members 
right away, bookkeeping ClassInfo data comes first.