diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index a049249b0..0429f5533 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -112,6 +112,7 @@ boost_hana_add_test(sandbox.function)
 boost_hana_add_test(sandbox.infix)
 boost_hana_add_test(sandbox.llist)
 boost_hana_add_test(sandbox.operator)
+boost_hana_add_test(sandbox.ratio)
 boost_hana_add_test(sandbox.sfinae)
 boost_hana_add_test(sandbox.string)
 boost_hana_add_test(sandbox.worksheet)
diff --git a/test/sandbox/ratio.cpp b/test/sandbox/ratio.cpp
new file mode 100644
index 000000000..cf6826f27
--- /dev/null
+++ b/test/sandbox/ratio.cpp
@@ -0,0 +1,170 @@
+/*
+@copyright Louis Dionne 2014
+Distributed under the Boost Software License, Version 1.0.
+(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
+ */
+
+#include <type_traits>
+
+
+constexpr struct sign_ {
+    template <typename X>
+    constexpr X operator()(X x) const {
+        return x < X{0}  ? -X{1} :
+               x == X{0} ?  X{0} :
+                            X{1} ;
+    }
+} sign{};
+
+constexpr struct abs_ {
+    template <typename X>
+    constexpr X operator()(X x) const {
+        return x * sign(x);
+    }
+} abs{};
+
+constexpr struct gcd_ {
+    template <typename X>
+    constexpr X operator()(X a, X b) const {
+        return b == X{0} ? a : (*this)(b, a % b);
+    }
+} gcd{};
+
+constexpr struct lcm_ {
+    template <typename X>
+    constexpr X operator()(X a, X b) const {
+        return a == X{0} && b == X{0} ? X{0} : (a / gcd(a, b)) * b;
+    }
+} lcm{};
+
+constexpr struct fac_ {
+    template <typename X>
+    constexpr X operator()(X n) const {
+        return n == X{0} ? X{1} : n * (*this)(n - X{1});
+    }
+} fac{};
+
+template <typename T>
+struct ratio {
+    T num, den;
+
+    constexpr ratio(T numerator, T denominator = T{1})
+        : num{sign(numerator) * sign(denominator) * abs(numerator) / gcd(numerator, denominator)},
+          den{abs(denominator) / gcd(numerator, denominator)}
+    { }
+
+    template <typename U>
+    constexpr ratio(ratio<U> other)
+        : ratio{other.num, other.den}
+    { }
+
+    constexpr ratio operator+() const {
+        return {num, den};
+    }
+
+    constexpr ratio operator-() const {
+        return {-num, den};
+    }
+
+    template <typename Ostream>
+    friend Ostream& operator<<(Ostream& os, ratio x) {
+        if (x.den == 1) return os << x.num;
+        else            return os << x.num << '/' << x.den;
+    }
+};
+
+template <typename X, typename Y>
+constexpr ratio<std::common_type_t<X, Y>> operator+(ratio<X> x, ratio<Y> y) {
+    return {x.num * y.den + x.den * y.num, x.den * y.den};
+}
+
+template <typename X, typename Y>
+constexpr auto operator-(ratio<X> x, ratio<Y> y) {
+    return x + (-y);
+}
+
+template <typename X, typename Y>
+constexpr ratio<std::common_type_t<X, Y>> operator*(ratio<X> x, ratio<Y> y) {
+    return {x.num * y.num, x.den * y.den};
+}
+
+template <typename X, typename Y>
+constexpr ratio<std::common_type_t<X, Y>> operator/(ratio<X> x, ratio<Y> y) {
+    return {x.num * y.den, x.den * y.num};
+}
+
+template <typename X, typename Y>
+constexpr bool operator==(ratio<X> x, ratio<Y> y) {
+    return x.num * y.den == y.num * x.den;
+}
+
+template <typename X, typename Y>
+constexpr bool operator!=(ratio<X> x, ratio<Y> y) {
+    return !(x == y);
+}
+
+
+template <typename X, typename Y>
+constexpr bool operator<(ratio<X> x, ratio<Y> y) {
+    return x.num * y.den < y.num * x.den;
+}
+
+template <typename X, typename Y>
+constexpr bool operator<=(ratio<X> x, ratio<Y> y) {
+    return !(y < x);
+}
+
+template <typename X, typename Y>
+constexpr bool operator>(ratio<X> x, ratio<Y> y) {
+    return y < x;
+}
+
+template <typename X, typename Y>
+constexpr bool operator>=(ratio<X> x, ratio<Y> y) {
+    return !(x < y);
+}
+
+
+constexpr ratio<unsigned long long> operator"" _r(unsigned long long num) {
+    return {num};
+}
+
+//////////////////////////////////////////////////////////////////////////////
+
+static_assert(sign(-100) == -1, "");
+static_assert(sign(0) == 0, "");
+static_assert(sign(20) == 1, "");
+
+static_assert(abs(0) == 0, "");
+static_assert(abs(20) == 20, "");
+static_assert(abs(-20) == 20, "");
+
+static_assert(gcd(3, 5) == 1, "");
+static_assert(gcd(5, 10) == 5, "");
+static_assert(gcd(8, 6) == 2, "");
+static_assert(gcd(8, 0) == 8, "");
+static_assert(gcd(0, 8) == 8, "");
+static_assert(gcd(0, 0) == 0, "");
+
+static_assert(lcm(0, 0) == 0, "");
+static_assert(lcm(1, 0) == 0, "");
+static_assert(lcm(0, 1) == 0, "");
+static_assert(lcm(2, 3) == 6, "");
+static_assert(lcm(2, 4) == 4, "");
+
+static_assert(fac(0) == 1, "");
+static_assert(fac(1) == 1 * 1, "");
+static_assert(fac(2) == 1 * 1 * 2, "");
+static_assert(fac(3) == 1 * 1 * 2 * 3, "");
+static_assert(fac(4) == 1 * 1 * 2 * 3 * 4, "");
+
+
+
+constexpr ratio<int> two{4, 2}, three{3};
+static_assert(two + three == 5_r, "");
+static_assert(two * three < 10_r, "");
+
+static_assert(1_r / 2_r == ratio<int>{1, 2}, "");
+
+
+int main() { }