Add TODOs

Author: james-d-mitchell

libsemigroups_pybind11/action.py

@@ -57,9 +57,11 @@
     may_return_wrapped_cxx_obj as _may_return_wrapped_cxx_obj,
     register_cxx_wrapped_type as _register_cxx_wrapped_type,
     to_cxx as _to_cxx,
-    to_py as _to_py,
+    to_py_new as _to_py,
 )
 
+from .detail.decorators import copydoc as _copydoc
+
 
 ########################################################################
 # Action python class
@@ -209,9 +211,7 @@ def __init__(
         if _to_cxx(self) is not None:
             return
         if len(args) != 0:
-            raise ValueError(
-                f"expected 0 positional arguments, but found {len(args)}"
-            )
+            raise ValueError(f"expected 0 positional arguments, but found {len(args)}")
         if not isinstance(generators, list):
             raise TypeError(
                 "expected the keyword argument 'generators' to be "
@@ -257,6 +257,17 @@ def __len__(self: _Self) -> int:
     def __contains__(self: _Self, pt: Point) -> bool:
         return self.position(pt) != _UNDEFINED
 
+    ########################################################################
+    # Iterators
+    ########################################################################
+
+    @_copydoc(_RightActionPPerm1PPerm1.generators)
+    def generators(self: _Self) -> Iterator[Element]:
+        return map(
+            _to_py,
+            _to_cxx(self).generators(),
+        )
+
 
 ########################################################################
 # Copy mem fns from sample C++ type and register types

libsemigroups_pybind11/detail/cxx_wrapper.py

@@ -131,9 +131,7 @@ def __getattr__(self: Self, name: str):
             def cxx_fn_wrapper(*args) -> Any:
                 if len(args) == 1 and isinstance(args[0], list):
                     args = args[0]
-                    return getattr(self._cxx_obj, name)(
-                        [to_cxx(x) for x in args]
-                    )
+                    return getattr(self._cxx_obj, name)([to_cxx(x) for x in args])
                 return getattr(self._cxx_obj, name)(*(to_cxx(x) for x in args))
 
             return cxx_fn_wrapper
@@ -164,6 +162,7 @@ def __eq__(self: Self, that) -> bool:
             )
         raise NameError("_cxx_obj has not been defined")
 
+    # TODO rm
     def _cxx_obj_type_from(self: Self, samples=(), types=()) -> Any:
         py_types = tuple([type(x) for x in samples] + list(types))
         lookup = self._py_template_params_to_cxx_type
@@ -199,9 +198,9 @@ def init_cxx_obj(self: Self, *args) -> None:
         defined.
         """
         assert self.py_template_params is not None
-        self._cxx_obj = self._py_template_params_to_cxx_type[
-            self.py_template_params
-        ](*(to_cxx(x) for x in args))
+        self._cxx_obj = self._py_template_params_to_cxx_type[self.py_template_params](
+            *(to_cxx(x) for x in args)
+        )
 
 
 # TODO proper annotations
@@ -217,9 +216,7 @@ def cxx_mem_fn_wrapper(self, *args):
         # TODO move the first if-clause into to_cxx?
         if len(args) == 1 and isinstance(args[0], list):
             args = [[to_cxx(x) for x in args[0]]]
-        result = getattr(to_cxx(self), cxx_mem_fn.__name__)(
-            *(to_cxx(x) for x in args)
-        )
+        result = getattr(to_cxx(self), cxx_mem_fn.__name__)(*(to_cxx(x) for x in args))
         if result is to_cxx(self):
             return self
         if type(result) in _CXX_WRAPPED_TYPE_TO_PY_TYPE:
@@ -265,8 +262,7 @@ def copy_cxx_mem_fns(cxx_class: pybind11_type, py_class: CxxWrapper) -> None:
     """
     for py_meth_name in dir(cxx_class):
         if (
-            (not py_meth_name.startswith("_"))
-            and py_meth_name not in dir(py_class)
+            (not py_meth_name.startswith("_")) and py_meth_name not in dir(py_class)
             # and type(getattr(cxx_class, py_meth_name)) is MethodType
         ):
             setattr(

src/action.cpp

@@ -208,20 +208,24 @@ Returns the number of generators.
 :rtype:
    int
 )pbdoc");
-      thing.def("generators",
-                &Action_::generators,
-                R"pbdoc(
-:sig=(self: Action) -> List[Element]:
+      thing.def(
+          "generators",
+          [](Action_ const& self) {
+            return py::make_iterator(self.generators().cbegin(),
+                                     self.generators().cend());
+          },
+          R"pbdoc(
+:sig=(self: Action) -> Iterator[Element]:
 
-Returns the list of generators.
+Returns an iterator yielding the generators.
 
 :complexity:
    Constant.
 
 :returns:
-   The generators.
+   An iterator yielding the generators.
 :rtype:
-   List[Element]
+   Iterator[Element]
 )pbdoc");
       thing.def("position",
                 &Action_::position,