add nanobind example

.gitignore

@@ -1 +1 @@
-*/build
+build

CMakeLists.txt

@@ -3,15 +3,20 @@ include(cmake/prefix.cmake)
 project(pycxx CXX)
 include(cmake/postfix.cmake)
 
-# set(FETCHCONTENT_UPDATES_DISCONNECTED ON)
+if(POLICY CMP0144)
+  cmake_policy(SET CMP0144 NEW)
+endif()
+set(FETCHCONTENT_UPDATES_DISCONNECTED ON)
 
 find_package(Python COMPONENTS Interpreter Development REQUIRED)
 find_package(Boost COMPONENTS python)
 
 include(pybind11)
+include(nanobind)
 FetchContent_MakeAvailable(${FetchContents})
 
 if(Boost_FOUND)
   add_subdirectory(boost)
 endif(Boost_FOUND)
 add_subdirectory(pybind11)
+add_subdirectory(nanobind)

README.md

@@ -4,6 +4,7 @@
 
 * boost: example for Boost.Python
 * pybind11: example for pybind11
+* nanobind: example for nanobind
 
 ## Boost.Python
 
@@ -13,15 +14,17 @@ It is assumed that the Boost.Python has been compiled and installed into some pl
 
 Pybind11 is a header-only library. It is automatically downloaded.
 
+## Nanobind
+
+Nanobind11 is automatically downloaded.
+
 ## How to build samples and run tests
 
 ```bash
 cd /somewhere/pycxx
-mkdir build
-cd build
-cmake ..
-make
-ctests
+cmake -B build
+cmake --build build
+cmake --build build --target test
 ```
 
 ## Options to cmake

cmake/nanobind.cmake

@@ -0,0 +1,7 @@
+include(FetchContent)
+FetchContent_Declare(
+  nanobind
+  GIT_REPOSITORY https://github.com/wjakob/nanobind.git
+  GIT_TAG b0e24d5b0ab0d518317d6b263a257ae72d4d29a2 # v1.5.2
+)
+list(APPEND FetchContents nanobind)

cmake/pybind11.cmake

@@ -2,6 +2,6 @@ include(FetchContent)
 FetchContent_Declare(
   pybind11
   GIT_REPOSITORY https://github.com/pybind/pybind11.git
-  GIT_TAG 8a099e44b3d5f85b20f05828d919d2332a8de841 # 2.11.1
+  GIT_TAG 8a099e44b3d5f85b20f05828d919d2332a8de841 # v2.11.1
 )
 list(APPEND FetchContents pybind11)

nanobind/CMakeLists.txt

@@ -0,0 +1,9 @@
+nanobind_add_module(nanobind_cxxmod add.hpp cxxmod.cpp)
+set_target_properties(nanobind_cxxmod PROPERTIES OUTPUT_NAME cxxmod CXX_STANDARD 17)
+
+configure_file(pytest.py.in pytest.py @ONLY)
+add_test(NAME nanobind_pytest COMMAND ${Python_EXECUTABLE} pytest.py)
+
+add_executable(nanobind_cxxtest cxxtest.cpp)
+set_target_properties(nanobind_cxxtest PROPERTIES OUTPUT_NAME cxxtest)
+add_test(NAME nanobind_cxxtest COMMAND cxxtest)

nanobind/add.hpp

@@ -0,0 +1,8 @@
+#ifndef ADD_HPP
+#define ADD_HPP
+
+inline int add(int i, int j) {
+    return i + j;
+}
+
+#endif // ADD_HPP

nanobind/cxxmod.cpp

@@ -0,0 +1,7 @@
+#include <nanobind/nanobind.h>
+#include "add.hpp"
+
+NB_MODULE(cxxmod, m) {
+  m.doc() = "nanobind example plugin";
+  m.def("add", &add, "Add two numbers");
+}

nanobind/cxxtest.cpp

@@ -0,0 +1,6 @@
+#include <iostream>
+#include "add.hpp"
+
+int main() {
+  std::cout << "add(1,2) = " << add(1,2) << std::endl;
+}

nanobind/pytest.py.in

@@ -0,0 +1,3 @@
+#!@Python_EXECUTABLE@
+import cxxmod
+print('add(1,2) = {}'.format(cxxmod.add(1,2)))

pybind11/pytest.py.in

@@ -1,3 +1,3 @@
-#!@PYTHON_EXECUTABLE@
+#!@Python_EXECUTABLE@
 import cxxmod
 print('add(1,2) = {}'.format(cxxmod.add(1,2)))