[libcxx-commits] [libcxx] [libc++][NFC] Simplify some overloads in fs::path a bit (PR #181053)

[via libcxx-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-libcxx

Author: Nikolas Klauser (philnik777)

<details>
<summary>Changes</summary>

We can use `if constexpr` instead, removing a bit of code and making things easier to read.

---
Full diff: https://github.com/llvm/llvm-project/pull/181053.diff


1 Files Affected:

- (modified) libcxx/include/__filesystem/path.h (+13-30) 


``````````diff
diff --git a/libcxx/include/__filesystem/path.h b/libcxx/include/__filesystem/path.h
index d567ff5dbb4f4..47ecf1ce19782 100644
--- a/libcxx/include/__filesystem/path.h
+++ b/libcxx/include/__filesystem/path.h
@@ -259,15 +259,14 @@ struct _PathCVT {
 
 template <>
 struct _PathCVT<__path_value> {
-  template <class _Iter, __enable_if_t<__has_exactly_input_iterator_category<_Iter>::value, int> = 0>
-  _LIBCPP_HIDE_FROM_ABI static void __append_range(__path_string& __dest, _Iter __b, _Iter __e) {
-    for (; __b != __e; ++__b)
-      __dest.push_back(*__b);
-  }
-
-  template <class _Iter, __enable_if_t<__has_forward_iterator_category<_Iter>::value, int> = 0>
+  template <class _Iter>
   _LIBCPP_HIDE_FROM_ABI static void __append_range(__path_string& __dest, _Iter __b, _Iter __e) {
-    __dest.append(__b, __e);
+    if constexpr (__has_forward_iterator_category<_Iter>::value) {
+      __dest.append(__b, __e);
+    } else {
+      for (; __b != __e; ++__b)
+        __dest.push_back(*__b);
+    }
   }
 
   template <class _Iter>
@@ -294,13 +293,7 @@ struct _PathCVT<char> {
     __char_to_wide(__str, const_cast<__path_value*>(__dest.data()) + __pos, __size);
   }
 
-  template <class _Iter, __enable_if_t<__has_exactly_input_iterator_category<_Iter>::value, int> = 0>
-  _LIBCPP_HIDE_FROM_ABI static void __append_range(__path_string& __dest, _Iter __b, _Iter __e) {
-    basic_string<char> __tmp(__b, __e);
-    __append_string(__dest, __tmp);
-  }
-
-  template <class _Iter, __enable_if_t<__has_forward_iterator_category<_Iter>::value, int> = 0>
+  template <class _Iter>
   _LIBCPP_HIDE_FROM_ABI static void __append_range(__path_string& __dest, _Iter __b, _Iter __e) {
     basic_string<char> __tmp(__b, __e);
     __append_string(__dest, __tmp);
@@ -874,23 +867,13 @@ class _LIBCPP_EXPORTED_FROM_ABI path {
   [[nodiscard]] iterator end() const;
 
 #  if _LIBCPP_HAS_LOCALIZATION
-  template <
-      class _CharT,
-      class _Traits,
-      __enable_if_t<is_same<_CharT, value_type>::value && is_same<_Traits, char_traits<value_type> >::value, int> = 0>
-  _LIBCPP_HIDE_FROM_ABI friend basic_ostream<_CharT, _Traits>&
-  operator<<(basic_ostream<_CharT, _Traits>& __os, const path& __p) {
-    __os << std::quoted(__p.native());
-    return __os;
-  }
-
-  template <
-      class _CharT,
-      class _Traits,
-      __enable_if_t<!is_same<_CharT, value_type>::value || !is_same<_Traits, char_traits<value_type> >::value, int> = 0>
+  template <class _CharT, class _Traits>
   _LIBCPP_HIDE_FROM_ABI friend basic_ostream<_CharT, _Traits>&
   operator<<(basic_ostream<_CharT, _Traits>& __os, const path& __p) {
-    __os << std::quoted(__p.string<_CharT, _Traits>());
+    if constexpr (is_same<_CharT, value_type>::value && is_same<_Traits, char_traits<value_type> >::value)
+      __os << std::quoted(__p.native());
+    else
+      __os << std::quoted(__p.string<_CharT, _Traits>());
     return __os;
   }
 

``````````

</details>


https://github.com/llvm/llvm-project/pull/181053