From 65885f505e76ebecd65ce8c4a52443702c0d3c09 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Fri, 27 Jan 2023 13:54:03 +0530
Subject: [PATCH] Use lambdas for template specialization

---
 src/calibre/utils/cpp_binding.h    | 11 ++++-------
 src/calibre/utils/windows/common.h |  6 ++----
 2 files changed, 6 insertions(+), 11 deletions(-)

diff --git a/src/calibre/utils/cpp_binding.h b/src/calibre/utils/cpp_binding.h
index 31bbc1dcd5..dd6c4a869a 100644
--- a/src/calibre/utils/cpp_binding.h
+++ b/src/calibre/utils/cpp_binding.h
@@ -17,7 +17,7 @@
 
 #define arraysz(x) (sizeof(x)/sizeof(x[0]))
 
-template<typename T, void free_T(void*), T null=static_cast<T>(NULL)>
+template<typename T, void free_T(T), T null=static_cast<T>(NULL)>
 class generic_raii {
 	private:
 		generic_raii( const generic_raii & ) noexcept;
@@ -45,8 +45,8 @@ class generic_raii {
 		explicit operator bool() const noexcept { return handle != null; }
 };
 
+class wchar_raii : public generic_raii<wchar_t*, [](wchar_t* x){PyMem_Free(x);}> {
 #if __cplusplus >= 201703L
-class wchar_raii : public generic_raii<wchar_t*, PyMem_Free> {
     private:
         Py_ssize_t sz;
     public:
@@ -58,13 +58,10 @@ class wchar_raii : public generic_raii<wchar_t*, PyMem_Free> {
         }
         std::wstring_view as_view() const { return std::wstring_view(handle, sz); }
         std::wstring as_copy() const { return std::wstring(handle, sz); }
-};
-#else
-typedef generic_raii<wchar_t*, PyMem_Free> wchar_raii;
 #endif
+};
 
-static inline void python_object_destructor(void *p) { PyObject *x = reinterpret_cast<PyObject*>(p); Py_XDECREF(x); }
-typedef generic_raii<PyObject*, python_object_destructor> pyobject_raii;
+typedef generic_raii<PyObject*, Py_DecRef> pyobject_raii;
 
 template<typename T, void free_T(void*), size_t sz, T null=static_cast<T>(NULL)>
 class generic_raii_array {
diff --git a/src/calibre/utils/windows/common.h b/src/calibre/utils/windows/common.h
index 3b5dcdf632..068bae1657 100644
--- a/src/calibre/utils/windows/common.h
+++ b/src/calibre/utils/windows/common.h
@@ -58,10 +58,8 @@ class scoped_com_initializer {  // {{{
 
 #define INITIALIZE_COM_IN_FUNCTION scoped_com_initializer com; if (!com) return com.set_python_error();
 
-static inline void co_task_mem_free(void* m) { CoTaskMemFree(m); }
-typedef generic_raii<wchar_t*, co_task_mem_free> com_wchar_raii;
-static inline void mapping_destructor(void *p) { UnmapViewOfFile(p); }
-typedef generic_raii<void*, mapping_destructor> mapping_raii;
+typedef generic_raii<wchar_t*, [](wchar_t *x) { CoTaskMemFree(x); }> com_wchar_raii;
+typedef generic_raii<void*, [](void* x) { UnmapViewOfFile(x);}> mapping_raii;
 
 class handle_raii {
 	private: