On Sunday, 11 June 2017 at 00:28:58 UTC, Andrei Alexandrescu
wrote:
// Also possible (no change to the language)
enum bool isInputRange(R) =
is(typeof((ref R r) => r)) && msg("must be copyable")
&& is(ReturnType!((R r) => r.empty) == bool) && msg("must
support bool empty")
&& is(typeof(lvalueOf!R.front)) && msg("must support front")
&& is(typeof(lvalueOf!R.popFront)) && msg("must support
back");
Andrei
What about using ddoc?
enum bool isInputRange(R) =
is(typeof((ref R r) => r)) /// must be copyable
&& is(ReturnType!((R r) => r.empty) == bool) /// must support
bool empty
&& is(typeof(lvalueOf!R.front)) /// must support front
&& is(typeof(lvalueOf!R.popFront)) /// must support back