On 09/03/2012 05:05 PM, bearophile wrote:
David Nadlinger:
Where would the real difference to ["struct", "class",
"union"].canFind(a) then? A sufficiently smart compiler (tm) could
optimize this to a efficient string "prefix switch statement" just as
well…
I think a smart compiler is not needed.
Maybe a general solution is to introduce a way to define overloaded
templates callable as functions, that get called if the input is a
literal (or statically known, but D design requires you to asks
explicitly for a CT evaluation):
void foo(static int[] a) {}
void foo(int[] a) {}
void main(string[] args) {
foo([1, 2]); // calls first foo
int[] a = [1, 2] ~ args.length;
foo(a); // calls second foo
}
Bye,
bearophile
It is not general enough. (and static is the wrong keyword.)
This would eventually lead to a solution like
bool among(S,T...)(S needle, auto enum T haystack){
...
foreach(h;haystack) static if(__traits(isConstant, h)){ ... }
...
}
Which is still rather specific.
Anyway, I don't consider among trying to be clever crucial at all.
