some new features

.venv/lib/python3.12/site-packages/Cython/Includes/libcpp/functional.pxd

@@ -0,0 +1,26 @@
+from libcpp cimport bool
+
+cdef extern from "<functional>" namespace "std" nogil:
+    cdef cppclass function[T]:
+        function() except +
+        function(T*) except +
+        function(function&) except +
+        function(void*) except +
+
+        function operator=(T*)
+        function operator=(function&)
+        function operator=(void*)
+        function operator=[U](U)
+
+        bool operator bool()
+
+    # Comparisons
+    cdef cppclass greater[T=*]:
+        # https://github.com/cython/cython/issues/3193
+        greater() except +
+        bool operator()(const T& lhs, const T& rhs) except +
+
+    cdef cppclass reference_wrapper[T]:
+        reference_wrapper()
+        reference_wrapper(T)
+        T& get() const