Rearrange sources (#4997)

include/xrpl/basics/ToString.h

@@ -0,0 +1,67 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of rippled: https://github.com/ripple/rippled
+    Copyright (c) 2012, 2013 Ripple Labs Inc.
+
+    Permission to use, copy, modify, and/or distribute this software for any
+    purpose  with  or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#ifndef RIPPLE_BASICS_TOSTRING_H_INCLUDED
+#define RIPPLE_BASICS_TOSTRING_H_INCLUDED
+
+#include <string>
+#include <type_traits>
+
+namespace ripple {
+
+/** to_string() generalizes std::to_string to handle bools, chars, and strings.
+
+    It's also possible to provide implementation of to_string for a class
+    which needs a string implementation.
+ */
+
+template <class T>
+typename std::enable_if<std::is_arithmetic<T>::value, std::string>::type
+to_string(T t)
+{
+    return std::to_string(t);
+}
+
+inline std::string
+to_string(bool b)
+{
+    return b ? "true" : "false";
+}
+
+inline std::string
+to_string(char c)
+{
+    return std::string(1, c);
+}
+
+inline std::string
+to_string(std::string s)
+{
+    return s;
+}
+
+inline std::string
+to_string(char const* s)
+{
+    return s;
+}
+
+}  // namespace ripple
+
+#endif