From 0b60d970e916540ccc9abc4706c2621e174a0481 Mon Sep 17 00:00:00 2001
From: Niels <niels.lohmann@gmail.com>
Date: Tue, 5 Apr 2016 22:12:12 +0200
Subject: [PATCH] make code independent of concrete locale

---
 src/json.hpp      | 17 +++++++++++++++--
 src/json.hpp.re2c | 17 +++++++++++++++--
 2 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/src/json.hpp b/src/json.hpp
index 13a6c49a..8f671fb0 100644
--- a/src/json.hpp
+++ b/src/json.hpp
@@ -88,6 +88,19 @@ struct has_mapped_type
     static constexpr bool value = sizeof(test<T>(0)) == 1;
 };
 
+/*!
+@brief helper class to create locales with decimal point
+@sa https://github.com/nlohmann/json/issues/51#issuecomment-86869315
+*/
+class DecimalSeparator : public std::numpunct<char>
+{
+  protected:
+    char do_decimal_point() const
+    {
+        return '.';
+    }
+};
+
 }
 
 /*!
@@ -6161,7 +6174,7 @@ class basic_json
                     {
                         // no exponent - output as a decimal
                         std::stringstream ss;
-                        ss.imbue(std::locale("C"));
+                        ss.imbue(std::locale(std::locale(), new DecimalSeparator));  // fix locale problems
                         ss << std::setprecision(m_type.bits.precision)
                            << std::fixed << m_value.number_float;
                         o << ss.str();
@@ -6182,7 +6195,7 @@ class basic_json
                         // to be safe, we read this value from
                         // std::numeric_limits<number_float_t>::digits10
                         std::stringstream ss;
-                        ss.imbue(std::locale("C"));
+                        ss.imbue(std::locale(std::locale(), new DecimalSeparator));  // fix locale problems
                         ss << std::setprecision(std::numeric_limits<double>::digits10)
                            << m_value.number_float;
                         o << ss.str();
diff --git a/src/json.hpp.re2c b/src/json.hpp.re2c
index 70079144..ebf83d83 100644
--- a/src/json.hpp.re2c
+++ b/src/json.hpp.re2c
@@ -88,6 +88,19 @@ struct has_mapped_type
     static constexpr bool value = sizeof(test<T>(0)) == 1;
 };
 
+/*!
+@brief helper class to create locales with decimal point
+@sa https://github.com/nlohmann/json/issues/51#issuecomment-86869315
+*/
+class DecimalSeparator : public std::numpunct<char>
+{
+  protected:
+    char do_decimal_point() const
+    {
+        return '.';
+    }
+};
+
 }
 
 /*!
@@ -6161,7 +6174,7 @@ class basic_json
                     {
                         // no exponent - output as a decimal
                         std::stringstream ss;
-                        ss.imbue(std::locale("C"));  // fix locale problems
+                        ss.imbue(std::locale(std::locale(), new DecimalSeparator));  // fix locale problems
                         ss << std::setprecision(m_type.bits.precision)
                            << std::fixed << m_value.number_float;
                         o << ss.str();
@@ -6182,7 +6195,7 @@ class basic_json
                         // to be safe, we read this value from
                         // std::numeric_limits<number_float_t>::digits10
                         std::stringstream ss;
-                        ss.imbue(std::locale("C"));  // fix locale problems
+                        ss.imbue(std::locale(std::locale(), new DecimalSeparator));  // fix locale problems
                         ss << std::setprecision(std::numeric_limits<double>::digits10)
                            << m_value.number_float;
                         o << ss.str();