From 513734611d2571a581e5f7d96aa527c06453354f Mon Sep 17 00:00:00 2001
From: James Lamb <jaylamb20@gmail.com>
Date: Mon, 25 Sep 2023 16:32:58 -0500
Subject: [PATCH] try fmt::format_string()

---
 include/LightGBM/utils/common.h | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/include/LightGBM/utils/common.h b/include/LightGBM/utils/common.h
index 00987740d14f..357a2df8fd89 100644
--- a/include/LightGBM/utils/common.h
+++ b/include/LightGBM/utils/common.h
@@ -1201,8 +1201,8 @@ inline static std::vector<T> StringToArray(const std::string& str, char delimite
 * /Users/jlamb/repos/LightGBM/include/LightGBM/utils/common.h:1203:35: error: 'format' is not a constant expression
 */
 template <typename T>
-inline static void format_to_buf(char* buffer, const size_t buf_len, const char* format, const T value) {
-    const auto result = fmt::format_to_n(buffer, buf_len, format, value);
+inline static void format_to_buf(char* buffer, const size_t buf_len, fmt::format_string<T> format, const T value) {
+    auto result = fmt::format_to_n(buffer, buf_len, format, value);
     if (result.size >= buf_len) {
       Log::Fatal("Numerical conversion failed. Buffer is too small.");
     }
@@ -1212,21 +1212,21 @@ inline static void format_to_buf(char* buffer, const size_t buf_len, const char*
 template<typename T, bool is_float, bool high_precision>
 struct __TToStringHelper {
   void operator()(T value, char* buffer, size_t buf_len) const {
-    format_to_buf(buffer, buf_len, "{}", value);
+    format_to_buf(buffer, buf_len, fmt::format_string<T>("{}"), value);
   }
 };
 
 template<typename T>
 struct __TToStringHelper<T, true, false> {
   void operator()(T value, char* buffer, size_t buf_len) const {
-    format_to_buf(buffer, buf_len, "{:g}", value);
+    format_to_buf(buffer, buf_len, fmt::format_string<T>("{:g}"), value);
   }
 };
 
 template<typename T>
 struct __TToStringHelper<T, true, true> {
   void operator()(T value, char* buffer, size_t buf_len) const {
-    format_to_buf(buffer, buf_len, "{:.17g}", value);
+    format_to_buf(buffer, buf_len, fmt::format_string<T>("{:.17g}"), value);
   }
 };
 
@@ -1234,7 +1234,7 @@ struct __TToStringHelper<T, true, true> {
 * Converts an array to a string with with values separated by the space character.
 * This method replaces Common's ``ArrayToString`` and ``ArrayToStringFast`` functionality
 * and is locale-independent.
-* 
+*
 * \note If ``high_precision_output`` is set to true,
 *       floating point values are output with more digits of precision.
 */