Converting a number to complex
Artur Skawina
art.08.09 at gmail.com
Sat Nov 24 02:30:40 PST 2012
On 11/24/12 08:27, Philippe Sigaud wrote:
> What's even nicer with an is() expr is that the introspection info is accessible when used inside a static if. So with Artur's code, CT can be seen inside the true branch of the static if.
Actually, static-ifs do not create a scope, so 'CT' leaks and is accessible
after it's defined, not just inside the static-if branch:
void main() {
Complex!double c;
static if (is(typeof(c) _ == Complex!CT, CT))
{}
writeln(CT.stringof);
}
It has to work like that, as otherwise it would be impossible (well, harder)
to conditionally compile /declarations/.
Unfortunately the is-expressions don't handle aliases properly, at least
with my old compiler here. So this does not work:
template isTempInst(alias TEMPL, T) {
static if (is(T _ == TEMPL!CT, CT))
enum isTempInst = true;
else
enum isTempInst = false;
}
artur
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