Reintroducing py::classh, this time as a simple alias for py::class_<U, py::smart_holder>.

include/pybind11/smart_holder.h

@@ -5,3 +5,18 @@
 #pragma once
 #pragma once
 
 
 #include "detail/smart_holder_type_casters.h"
 #include "detail/smart_holder_type_casters.h"
+#include "pybind11.h"
+
+PYBIND11_NAMESPACE_BEGIN(PYBIND11_NAMESPACE)
+
+// Supports easier switching between py::class_<U> and py::class_<U, py::smart_holder>:
+// users can simply replace the `_` in `class_` with `h` or vice versa.
+// Note though that the PYBIND11_SMART_HOLDER_TYPE_CASTERS(U) macro also needs to be
+// added (for `classh`) or commented out (for `class_`).
+template <typename type_, typename... options>
+class classh : public class_<type_, smart_holder, options...> {
+public:
+    using class_<type_, smart_holder, options...>::class_;
+};
+
+PYBIND11_NAMESPACE_END(PYBIND11_NAMESPACE)

tests/class_sh_module_local_1.cpp

@@ -22,7 +22,7 @@ PYBIND11_MODULE(class_sh_module_local_1, m) {
     namespace py = pybind11;
     namespace py = pybind11;
     using namespace pybind11_tests::class_sh_module_local;
     using namespace pybind11_tests::class_sh_module_local;
 
 
-    py::class_<atyp, py::smart_holder>(m, "atyp", py::module_local())
+    py::classh<atyp>(m, "atyp", py::module_local())
         .def(py::init([](const std::string &mtxt) {
         .def(py::init([](const std::string &mtxt) {
             atyp obj;
             atyp obj;
             obj.mtxt = mtxt;
             obj.mtxt = mtxt;

tests/class_sh_module_local_2.cpp

@@ -22,7 +22,7 @@ PYBIND11_MODULE(class_sh_module_local_2, m) {
     namespace py = pybind11;
     namespace py = pybind11;
     using namespace pybind11_tests::class_sh_module_local;
     using namespace pybind11_tests::class_sh_module_local;
 
 
-    py::class_<atyp, py::smart_holder>(m, "atyp", py::module_local())
+    py::classh<atyp>(m, "atyp", py::module_local())
         .def(py::init([](const std::string &mtxt) {
         .def(py::init([](const std::string &mtxt) {
             atyp obj;
             atyp obj;
             obj.mtxt = mtxt;
             obj.mtxt = mtxt;

tests/test_class_sh_basic.cpp

@@ -57,9 +57,7 @@ namespace class_sh_basic {
 TEST_SUBMODULE(class_sh_basic, m) {
 TEST_SUBMODULE(class_sh_basic, m) {
     namespace py = pybind11;
     namespace py = pybind11;
 
 
-    py::class_<atyp, py::smart_holder>(m, "atyp")
-        .def(py::init<>())
-        .def(py::init([](const std::string &mtxt) {
+    py::classh<atyp>(m, "atyp").def(py::init<>()).def(py::init([](const std::string &mtxt) {
         atyp obj;
         atyp obj;
         obj.mtxt = mtxt;
         obj.mtxt = mtxt;
         return obj;
         return obj;

tests/test_class_sh_inheritance.cpp

@@ -73,8 +73,8 @@ namespace pybind11_tests {
 namespace class_sh_inheritance {
 namespace class_sh_inheritance {
 
 
 TEST_SUBMODULE(class_sh_inheritance, m) {
 TEST_SUBMODULE(class_sh_inheritance, m) {
-    py::class_<base, py::smart_holder>(m, "base");
-    py::class_<drvd, base, py::smart_holder>(m, "drvd");
+    py::classh<base>(m, "base");
+    py::classh<drvd, base>(m, "drvd");
 
 
     auto rvto = py::return_value_policy::take_ownership;
     auto rvto = py::return_value_policy::take_ownership;
 
 
@@ -89,9 +89,9 @@ TEST_SUBMODULE(class_sh_inheritance, m) {
     m.def("pass_shcp_drvd", pass_shcp_drvd);
     m.def("pass_shcp_drvd", pass_shcp_drvd);
 
 
     // __init__ needed for Python inheritance.
     // __init__ needed for Python inheritance.
-    py::class_<base1, py::smart_holder>(m, "base1").def(py::init<>());
-    py::class_<base2, py::smart_holder>(m, "base2").def(py::init<>());
-    py::class_<drvd2, base1, base2, py::smart_holder>(m, "drvd2");
+    py::classh<base1>(m, "base1").def(py::init<>());
+    py::classh<base2>(m, "base2").def(py::init<>());
+    py::classh<drvd2, base1, base2>(m, "drvd2");
 
 
     m.def("rtrn_mptr_drvd2", rtrn_mptr_drvd2, rvto);
     m.def("rtrn_mptr_drvd2", rtrn_mptr_drvd2, rvto);
     m.def("rtrn_mptr_drvd2_up_cast1", rtrn_mptr_drvd2_up_cast1, rvto);
     m.def("rtrn_mptr_drvd2_up_cast1", rtrn_mptr_drvd2_up_cast1, rvto);

tests/test_class_sh_unique_ptr_member.cpp

@@ -46,9 +46,7 @@ namespace pybind11_tests {
 namespace class_sh_unique_ptr_member {
 namespace class_sh_unique_ptr_member {
 
 
 TEST_SUBMODULE(class_sh_unique_ptr_member, m) {
 TEST_SUBMODULE(class_sh_unique_ptr_member, m) {
-    py::class_<pointee, py::smart_holder>(m, "pointee")
-        .def(py::init<>())
-        .def("get_int", &pointee::get_int);
+    py::classh<pointee>(m, "pointee").def(py::init<>()).def("get_int", &pointee::get_int);
 
 
     m.def("make_unique_pointee", make_unique_pointee);
     m.def("make_unique_pointee", make_unique_pointee);