experimentally use wchar and wstring in parser.hpp

toml/parser.hpp

@@ -1057,6 +1057,34 @@ struct parse_data
 
 };
 
+#ifdef _MSC_VER
+
+template<typename traits = std::char_traits<wchar_t>>
+toml::Table parse(std::basic_istream<wchar_t, traits>& is)
+{
+    const auto curloc = is.getloc();
+    is.imbue(std::locale(std::locale::empty(), new std::codecvt_utf8<wchar_t>));
+
+    const auto initial = is.tellg();
+    is.seekg(0, std::ios::end);
+    const auto eofpos  = is.tellg();
+    const std::size_t size = eofpos - initial;
+    is.seekg(initial);
+
+    std::vector<wchar_t> contents(size);
+    is.read(contents.data(), size);
+    is.imbue(curloc);
+    return parse_data::invoke(contents.cbegin(), contents.cend());
+}
+
+toml::Table parse(const std::string& filename)
+{
+    std::wifstream ifs(filename);
+    if(!ifs.good()) throw std::runtime_error("file open error: " + filename);
+    return parse(ifs);
+}
+
+#else
 template<typename traits = std::char_traits<toml::character>>
 toml::Table parse(std::basic_istream<toml::character, traits>& is)
 {
@@ -1076,6 +1104,7 @@ toml::Table parse(const std::string& filename)
     if(!ifs.good()) throw std::runtime_error("file open error: " + filename);
     return parse(ifs);
 }
+#endif
 
 
 }// toml