From 2383e6d0f29c95587bf49890af10f0b8557a8cd1 Mon Sep 17 00:00:00 2001
From: Kefu Chai <tchaikov@gmail.com>
Date: Sun, 10 Sep 2023 20:28:52 +0800
Subject: [PATCH] Revert "node/convert: relax the check for string_view
 (#1222)" (#1225)

This reverts commit 6262201182a0ee357d8a456e6d1a8e5984e4c6dd.

in 62622011, we wanted address the needs to use the `string_view`
converter in C++98, but that requirement was based on wrong
preconditions. `std::string_view` was introduced in C++17, and
popular standard libraries like libstdc++ and libc++ both provide
`std::string_view` when the source is built with C++17.

furthermore 62622011 is buggy. because it uses `<version>` to tell
the feature set provided by the standard library. but `<version>`
is a part of C++20. so this defeats the purpose of the change of
62622011.

Fixes #1223
---
 include/yaml-cpp/node/convert.h | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/include/yaml-cpp/node/convert.h b/include/yaml-cpp/node/convert.h
index 9dea370..d0eb450 100644
--- a/include/yaml-cpp/node/convert.h
+++ b/include/yaml-cpp/node/convert.h
@@ -17,9 +17,8 @@
 #include <type_traits>
 #include <valarray>
 #include <vector>
-#include <version>
 
-#ifdef __cpp_lib_string_view
+#if __cplusplus >= 201703L
 #include <string_view>
 #endif
 
@@ -94,7 +93,7 @@ struct convert<char[N]> {
   static Node encode(const char* rhs) { return Node(rhs); }
 };
 
-#ifdef __cpp_lib_string_view
+#if __cplusplus >= 201703L
 template <>
 struct convert<std::string_view> {
   static Node encode(std::string_view rhs) { return Node(std::string(rhs)); }