print: pair.hpp: default printer for std::pair<>

include/xo/indentlog/print/pair.hpp

@@ -0,0 +1,24 @@
+/* @file pair.hpp */
+
+#pragma once
+
+#include <iostream>
+#include <utility>
+
+namespace std {
+    template <typename T, typename U>
+    inline std::ostream &
+    operator<<(std::ostream & os,
+               std::pair<T,U> const & x)
+    {
+        os << "["
+           << x.first
+           << " "
+           << x.second
+           << "]";
+
+        return os;
+    } /*operator<<*/
+} /*namespace std*/
+
+/* end pair.hpp */