Warning on template parameter identifier shadowing?

H. S. Teoh hsteoh at quickfur.ath.cx
Wed Aug 5 16:57:43 UTC 2020

On Wed, Aug 05, 2020 at 04:35:12PM +0000, Paul Backus via Digitalmars-d wrote:
> [...] there's no reliable way to generate unique identifiers at
> compile time.)

Sure there is. Well, depending on what you need said identifiers for,
that is.  Given a unique tuple, a template instantiated with that tuple
is a unique identifier for that tuple.

I've used this fact to generate unique identifiers for temporaries in
static foreach loops, since static foreach does not introduce a new
scope, so all iterations share the same namespace, and any temporaries
you might declare will collide with other iterations and fail with a
compile error. To work around this, I wrap the desired declaration(s) in
an auxiliary template that gets instantiated with the index variable of
the static foreach, thus guaranteeing uniqueness:

	struct TmpStruct(int iter) {

	int someAcc;
	switch (someVar) {
		static foreach (i; 0 .. 99) {
			case i:
				auto tmp = TmpStruct!i(...);


Long, long ago, the ancient Chinese invented a device that lets them see through walls. It was called the "window".

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