Add 'xo-pyutil/' from commit 'a2cb8ae60f'

git-subtree-dir: xo-pyutil
git-subtree-mainline: 219038c445
git-subtree-split: a2cb8ae60f

xo-pyutil/example/CMakeLists.txt

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+add_subdirectory(ex1)

xo-pyutil/example/ex1/CMakeLists.txt

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+# xo-pyutil/example/ex1/CMakeLists.txt
+
+set(SELF_LIB xo_pyutilexample)
+set(SELF_SRCS pyex1.cpp)
+
+if (XO_ENABLE_EXAMPLES)
+    xo_pybind11_library(${SELF_LIB} ${PROJECT_NAME}Targets ${SELF_SRCS})
+    xo_pybind11_dependency(${SELF_LIB} refcnt)
+endif()
+
+# end CMakeLists.txt

xo-pyutil/example/ex1/pyex1.cpp

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+/* @file pyex1.cpp */
+
+#include "pyutilexample.hpp"
+#include "xo/pyutil/pyutil.hpp"
+#include <cmath>
+
+namespace xo {
+
+    PYBIND11_MODULE(XO_PYUTILEXAMPLE_MODULE_NAME(), m) {
+        m.def("sqrt", [](double x) { return ::sqrt(x); });
+    }
+}
+
+/* end pyex1.cpp */

xo-pyutil/example/ex1/pyutilexample.hpp.in

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+/* @file pyutilexample.hpp */
+
+/* python requires module name = library name
+ * example:
+ *   PYBIND11_MODULE(XO_PYUTILEXAMPLE_MODULE_NAME(), m) { ... }
+ */
+#define XO_PYUTILEXAMPLE_MODULE_NAME() @SELF_LIB@
+
+/* example:
+ *   py::module_::import(XO_PYUTILEXAMPLE_MODULE_NAME_STR)
+ */
+#define XO_PYUTILEXAMPLE_MODULE_NAME_STR "@SELF_LIB@"
+
+/* example:
+ *   XO_PYUTILEXAMPLE_IMPORT_MODULE()
+ * replaces
+ *   py::module_::import("xo_pyexpression")
+ */
+#define XO_PYUTILEXAMPLE_IMPORT_MODULE() py::module_::import("@SELF_LIB@")
+
+/* end pyutilexample.hpp */