static bool containsIC(Collection<S> l, S s) {
  ret containsIgnoreCase(l, s);
}

static bool containsIC(S[] l, S s) {
  ret containsIgnoreCase(l, s);
}

static bool containsIC(S s, char c) {
  ret containsIgnoreCase(s, c);
}

static boolean containsIC(S a, S b) {
  ret containsIgnoreCase(a, b);
}

ifclass Producer
sbool containsIC(Producer<S> p, S a) {
  if (p != null && a != null) while true {
    S x = p.next();
    if (x == null) break;
    if (eqic(x, a)) true;
  }
  false;
}
endif

Began life as a copy of #1003329