refs #18, fighting VS2015 sfinae issues

Author: gulrak

examples/dir.cpp

@@ -1,17 +1,21 @@
-#include <iostream>
-#include <iomanip>
 #include <chrono>
+#include <iomanip>
+#include <iostream>
 #include <string>
 
-#if defined(__cplusplus) && __cplusplus >= 201703L && defined(__has_include) && __has_include(<filesystem>)
+#if defined(__cplusplus) && __cplusplus >= 201703L && defined(__has_include)
+#if __has_include(<filesystem>)
 #include <filesystem>
 namespace fs = std::filesystem;
-#else
+#define GHC_USE_STD_FS
+#endif
+#endif
+#ifndef GHC_USE_STD_FS
 #include <ghc/filesystem.hpp>
 namespace fs = ghc::filesystem;
 #endif
 
-template<typename TP>
+template <typename TP>
 std::time_t to_time_t(TP tp)
 {
     // Based on trick from: Nico Josuttis, C++17 - The Complete Guide
@@ -23,8 +27,8 @@ static std::string perm_to_str(fs::perms prms)
 {
     std::string result;
     result.reserve(9);
-    for(int i = 0; i < 9; ++i) {
-        result = ((static_cast<int>(prms) & (1<<i)) ? "xwrxwrxwr"[i] : '-') + result;
+    for (int i = 0; i < 9; ++i) {
+        result = ((static_cast<int>(prms) & (1 << i)) ? "xwrxwrxwr"[i] : '-') + result;
     }
     return result;
 }
@@ -33,27 +37,24 @@ int main(int argc, char* argv[])
 {
 #ifdef GHC_FILESYSTEM_VERSION
     fs::u8arguments u8guard(argc, argv);
-    if(!u8guard.valid()) {
+    if (!u8guard.valid()) {
         std::cerr << "Invalid character encoding, UTF-8 based encoding needed." << std::endl;
         std::exit(EXIT_FAILURE);
     }
 #endif
-    if(argc > 2) {
+    if (argc > 2) {
         std::cerr << "USAGE: dir <path>" << std::endl;
         exit(1);
     }
     fs::path dir{"."};
-    if(argc == 2) {
+    if (argc == 2) {
         dir = fs::u8path(argv[1]);
     }
-    for(auto de : fs::directory_iterator(dir)) {
+    for (auto de : fs::directory_iterator(dir)) {
         auto ft = to_time_t(de.last_write_time());
         auto ftm = *std::localtime(&ft);
-        std::cout << (de.is_directory() ? "d" : "-") << perm_to_str(de.symlink_status().permissions()) << "  "
-                  << std::setw(8) << (de.is_directory() ? "-" : std::to_string(de.file_size())) << "  "
-                  << std::put_time(&ftm, "%Y-%m-%d %H:%M:%S") << "  "
-                  << de.path().filename().string() 
-                  << std::endl;
+        std::cout << (de.is_directory() ? "d" : "-") << perm_to_str(de.symlink_status().permissions()) << "  " << std::setw(8) << (de.is_directory() ? "-" : std::to_string(de.file_size())) << "  " << std::put_time(&ftm, "%Y-%m-%d %H:%M:%S") << "  "
+                  << de.path().filename().string() << std::endl;
     }
     return 0;
 }

examples/du.cpp

@@ -2,10 +2,14 @@
 #include <iomanip>
 #include <chrono>
 
-#if defined(__cplusplus) && __cplusplus >= 201703L && defined(__has_include) && __has_include(<filesystem>)
+#if defined(__cplusplus) && __cplusplus >= 201703L && defined(__has_include)
+#if __has_include(<filesystem>)
 #include <filesystem>
 namespace fs = std::filesystem;
-#else
+#define GHC_USE_STD_FS
+#endif
+#endif
+#ifndef GHC_USE_STD_FS
 #include <ghc/filesystem.hpp>
 namespace fs = ghc::filesystem;
 #endif

include/ghc/filesystem.hpp

@@ -1296,13 +1296,13 @@ inline StringType fromUtf8(const std::string& utf8String, const typename StringT
     return result;
 }
 
-template <typename charT, typename traits, typename Alloc, typename std::enable_if<(sizeof(charT) == 1)>::type* = nullptr>
+template <typename charT, typename traits, typename Alloc, typename std::enable_if<(sizeof(charT) == 1), int>::type size = 1>
 inline std::string toUtf8(const std::basic_string<charT, traits, Alloc>& unicodeString)
 {
     return std::string(unicodeString.begin(), unicodeString.end());
 }
 
-template <typename charT, typename traits, typename Alloc, typename std::enable_if<(sizeof(charT) == 2)>::type* = nullptr>
+template <typename charT, typename traits, typename Alloc, typename std::enable_if<(sizeof(charT) == 2), int>::type size = 2>
 inline std::string toUtf8(const std::basic_string<charT, traits, Alloc>& unicodeString)
 {
     std::string result;
@@ -1324,7 +1324,7 @@ inline std::string toUtf8(const std::basic_string<charT, traits, Alloc>& unicode
     return result;
 }
 
-template <typename charT, typename traits, typename Alloc, typename std::enable_if<(sizeof(charT) == 4)>::type* = nullptr>
+template <typename charT, typename traits, typename Alloc, typename std::enable_if<(sizeof(charT) == 4), int>::type size = 4>
 inline std::string toUtf8(const std::basic_string<charT, traits, Alloc>& unicodeString)
 {
     std::string result;
@@ -1334,10 +1334,10 @@ inline std::string toUtf8(const std::basic_string<charT, traits, Alloc>& unicode
     return result;
 }
 
-template <typename SourceType>
-inline std::string toUtf8(const SourceType* unicodeString)
+template <typename charT>
+inline std::string toUtf8(const charT* unicodeString)
 {
-    return toUtf8(std::basic_string<SourceType, std::char_traits<SourceType>>(unicodeString));
+    return toUtf8(std::basic_string<charT, std::char_traits<charT>>(unicodeString));
 }
 
 }  // namespace detail