using enums for flags

[Trass3r]

So I was just reading  
http://stackoverflow.com/questions/1448396/how-to-use-enums-as-flags-in-c

And did a quick test:

enum STC
{
	A = 0x1,
	B = 0x2,
	C = 0x4
}
enum FOO
{
	F = 0x8,
	G = 0x10
}

void main()
{
	STC s = STC.A | STC.C;
	STC s2 = s & STC.A;
	auto s2_2 = s & STC.A;
	static assert(is(typeof(s2_2) == STC));

	static assert(!__traits(compiles, { if (s & FOO.F) {} }));       //  
fails. that one's hard to track down
	static assert(!__traits(compiles, { auto s3 = s & FOO.F; }));    //  
fails, cause implicitly converts to int
	static assert(!__traits(compiles, { STC s4 = s & FOO.F; }));
	static assert(!__traits(compiles, { FOO s5 = s & FOO.F; }));

	static assert(!__traits(compiles, { STC t = STC.A | FOO.F; }));
	static assert(!__traits(compiles, { auto t = STC.A | FOO.F; })); // fails

	static assert(!__traits(compiles, { if (s & STC.B == 0) {} }));  //  
works, but error not gagged
	static assert(!__traits(compiles, { if (s && STC.B) {} }));      // fails
}

Does it really make sense to allow bitwise operations on different enums?
There should at least be some way to get this straight without having to  
resort to a heap of code like in C++:  
http://www.artima.com/cppsource/safelabels.html