auto s = "One 2 three 42";
auto r = `(\d+)`;
assert(s.extractCapture (r).equal(["2", "42"]));
assert(s.extractCapture!int(r).equal([ 2 , 42 ]));
auto s = "2.3 4.56 78.9";
auto r = `(\d+)\.(\d+)`;
assert(s.extractCapture!(int, int)(r).equal([tuple(2, 3), tuple(4, 56), tuple(78, 9)]));