From 6f46998b327daebd32a33d0cc34b93a8a1863024 Mon Sep 17 00:00:00 2001
From: Peter Newman <peternewman@users.noreply.github.com>
Date: Sat, 18 Apr 2026 16:28:18 +0100
Subject: [PATCH] Revert "Replace deprecated pre-C++11 code (#1890)"

This reverts commit 597672a03a8aec5d12ff71ddeffbd571f26d5ebb.
---
 common/utils/StringUtils.cpp | 4 ++--
 include/ola/ExportMap.h      | 3 ++-
 include/olad/Plugin.h        | 3 ++-
 3 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/common/utils/StringUtils.cpp b/common/utils/StringUtils.cpp
index d01ac72e12..749ad79676 100644
--- a/common/utils/StringUtils.cpp
+++ b/common/utils/StringUtils.cpp
@@ -454,12 +454,12 @@ bool HexStringToInt(const string &value, int64_t *output) {
 
 void ToLower(string *s) {
   std::transform(s->begin(), s->end(), s->begin(),
-                 [](int value){return std::tolower(value);});
+                 std::ptr_fun<int, int>(std::tolower));
 }
 
 void ToUpper(string *s) {
   std::transform(s->begin(), s->end(), s->begin(),
-                 [](int value){return std::toupper(value);});
+                 std::ptr_fun<int, int>(std::toupper));
 }
 
 void CapitalizeLabel(string *s) {
diff --git a/include/ola/ExportMap.h b/include/ola/ExportMap.h
index 3e4e810d46..284eb9ae3d 100644
--- a/include/ola/ExportMap.h
+++ b/include/ola/ExportMap.h
@@ -77,7 +77,8 @@ class BaseVariable {
   std::string m_name;
 };
 
-struct VariableLessThan {
+struct VariableLessThan: public std::binary_function<BaseVariable*,
+                                                     BaseVariable*, bool> {
   bool operator()(BaseVariable *x, BaseVariable *y) {
     return x->Name() < y->Name();
   }
diff --git a/include/olad/Plugin.h b/include/olad/Plugin.h
index 163e0ad772..623718a2ca 100644
--- a/include/olad/Plugin.h
+++ b/include/olad/Plugin.h
@@ -107,7 +107,8 @@ class AbstractPlugin {
 };
 
 
-struct PluginLessThan {
+struct PluginLessThan: public std::binary_function<AbstractPlugin*,
+                                                   AbstractPlugin*, bool> {
   bool operator()(AbstractPlugin *x, AbstractPlugin *y) {
     return x->Id() < y->Id();
   }