[libcxx-commits] [libcxx] WIP - [libc++][string] P2587R3: `to_string` or not `to_string` (PR #78100)

[A. Jiang via libcxx-commits]

================
@@ -247,6 +248,36 @@ long double stold(const wstring& str, size_t* idx) { return as_float<long double
 
 // to_string
 
+#if _LIBCPP_STD_VER >= 26
+
+string to_string(int val) { return std::format("{}", val); }
+string to_string(long val) { return std::format("{}", val); }
+string to_string(long long val) { return std::format("{}", val); }
+string to_string(unsigned val) { return std::format("{}", val); }
+string to_string(unsigned long val) { return std::format("{}", val); }
+string to_string(unsigned long long val) { return std::format("{}", val); }
+
+#  ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
+wstring to_wstring(int val) { return std::format(L"{}", val); }
+wstring to_wstring(long val) { return std::format(L"{}", val); }
+wstring to_wstring(long long val) { return std::format(L"{}", val); }
+wstring to_wstring(unsigned val) { return std::format(L"{}", val); }
+wstring to_wstring(unsigned long val) { return std::format(L"{}", val); }
+wstring to_wstring(unsigned long long val) { return std::format(L"{}", val); }
+#  endif
----------------
frederick-vs-ja wrote:

I believe overloads for integer types shouldn't be changed. They are efficient enough and already meeting the C++26 requirements (not accessing C locale) since commit 141c2b768db09569cfa227bd258be41593ba206d. And IIUC using `std::format` here will be a bit perssimizing.

https://github.com/llvm/llvm-project/pull/78100