From 8d461d793e3619f1e9e9eaa03dac668a10db5a33 Mon Sep 17 00:00:00 2001
From: Dmitry Kokorin <dmitry@kokorin.org>
Date: Wed, 16 Mar 2016 00:44:19 +0300
Subject: [PATCH] space_age: iteration 1, X-macros version

---
 cpp/space-age/space_age.cpp | 56 +++++++++++++------------------------
 1 file changed, 20 insertions(+), 36 deletions(-)

diff --git a/cpp/space-age/space_age.cpp b/cpp/space-age/space_age.cpp
index 1bad6c9..70780a8 100644
--- a/cpp/space-age/space_age.cpp
+++ b/cpp/space-age/space_age.cpp
@@ -2,6 +2,25 @@
 
 namespace space_age {
 
+#define PLANET_TABLE                \
+    X(on_mercury,   0.2408467)      \
+    X(on_venus,     0.61519726)     \
+    X(on_mars,      1.8808158)      \
+    X(on_jupiter,   11.862615)      \
+    X(on_saturn,    29.447498)      \
+    X(on_uranus,    84.016846)      \
+    X(on_neptune,   164.79132)
+
+#define X(a, b)                     \
+    double space_age:: a () const   \
+    {                               \
+        return on_earth() / b;      \
+    }
+
+    PLANET_TABLE
+#undef X
+
+
 space_age::space_age(double seconds)
   : seconds_(seconds)
 {
@@ -12,44 +31,9 @@ double space_age::seconds() const
     return seconds_;
 }
 
-double space_age::on_earth()   const
+double space_age::on_earth() const
 {
     return seconds() / 31557600;
 }
 
-double space_age::on_mercury() const
-{
-    return on_earth() / 0.2408467;
-}
-
-double space_age::on_venus()   const
-{
-    return on_earth() / 0.61519726;
-}
-
-double space_age::on_mars()    const
-{
-    return on_earth() / 1.8808158;
-}
-
-double space_age::on_jupiter() const
-{
-    return on_earth() / 11.862615;
-}
-
-double space_age::on_saturn()  const
-{
-    return on_earth() / 29.447498;
-}
-
-double space_age::on_uranus()  const
-{
-    return on_earth() / 84.016846;
-}
-
-double space_age::on_neptune() const
-{
-    return on_earth() / 164.79132;
-}
-
 }