• Dominic Jones (22/22) Nov 30 2018 Hello,
• Stanislav Blinov (15/22) Nov 30 2018 You can use __FILE__ and __LINE__. The only limitation there is,

Dominic Jones <dominic.jones gmx.co.uk> writes:

Hello,

I would like to transliterate the following code, below, to D, 
but it seems to be more difficult than I expected.

I cannot find a keyword, like __COUNTER__, that would enable the 
construction of unique types each time UQ is used. Even if such a 
keyword did exist, I cannot find a way wrap it such that I can 
have statements like "auto c0 = UQ(3);".

Any suggestions would be appreciated.

(This question is related to 
https://forum.dlang.org/thread/gqzlchurxylkvwiirrxb forum.dlang.org)


template<std::size_t ID, typename T>
struct Unique { T value; };

// Would prefer something like "__CPU_CLOCK_TICKS__"
// instead of __COUNTER__, if it were available
#define UQ(v) Unique<__COUNTER__, decltype(v)>{v}

int main()
{
   auto c0 = UQ(3);
   auto c1 = UQ(4);
   static_assert(!std::is_same<decltype(c0), decltype(c1)>::value);
}

(at: https://godbolt.org/z/O7lt5f)

Stanislav Blinov <stanislav.blinov gmail.com> writes:

On Friday, 30 November 2018 at 15:27:07 UTC, Dominic Jones wrote:
 Hello,

 I would like to transliterate the following code, below, to D, 
 but it seems to be more difficult than I expected.

 I cannot find a keyword, like __COUNTER__, that would enable 
 the construction of unique types each time UQ is used. Even if 
 such a keyword did exist, I cannot find a way wrap it such that 
 I can have statements like "auto c0 = UQ(3);".

You can use __FILE__ and __LINE__. The only limitation there is, 
obviously, one declaration per line.

struct Unique(T, string file, size_t line) {
     T value;
}

auto UQ(T, string file = __FILE__, size_t line = __LINE__)(auto 
ref T value) {
     return Unique!(T, file, line)(value);
}

void main() {
     auto c0 = UQ(3);
     auto c1 = UQ(4);
     static assert(!is(typeof(c0) == typeof(c1)));
}