LSST Applications g044012fb7c+304891ab8a,g04a91732dc+4e1b87f259,g07dc498a13+f701f15b83,g114c6a66ad+c7887c1284,g1409bbee79+f701f15b83,g1a7e361dbc+f701f15b83,g1fd858c14a+6ebd102b59,g35bb328faa+0eb18584fe,g3bd4b5ce2c+e83bf4edc8,g4e0f332c67+976ceb6bc8,g53246c7159+0eb18584fe,g5477a8d5ce+51234355ef,g60b5630c4e+c7887c1284,g623d845a50+c7887c1284,g6f0c2978f1+98123c34b6,g71fabbc107+c7887c1284,g75b6c65c88+ce466f4385,g78460c75b0+85633614c8,g786e29fd12+02b9b86fc9,g8852436030+cfe5cf5b7b,g89139ef638+f701f15b83,g9125e01d80+0eb18584fe,g95236ca021+d4f98599f0,g974caa22f6+0eb18584fe,g989de1cb63+f701f15b83,g9f33ca652e+b4908f5dcd,gaaedd4e678+f701f15b83,gabe3b4be73+543c3c03c9,gace736f484+07e57cea59,gb1101e3267+487fd1b06d,gb58c049af0+492386d360,gc99c83e5f0+a513197d39,gcf25f946ba+cfe5cf5b7b,gd0fa69b896+babbe6e5fe,gd6cbbdb0b4+3fef02d88a,gde0f65d7ad+e8379653a2,ge278dab8ac+ae64226a64,gfba249425e+0eb18584fe,w.2025.07
LSST Data Management Base Package
Loading...
Searching...
No Matches
TemplateInvoker.h
Go to the documentation of this file.
1// -*- lsst-c++ -*-
2/*
3 * LSST Data Management System
4 * See COPYRIGHT file at the top of the source tree.
5 *
6 * This product includes software developed by the
7 * LSST Project (http://www.lsst.org/).
8 *
9 * This program is free software: you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation, either version 3 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the LSST License Statement and
20 * the GNU General Public License along with this program. If not,
21 * see <http://www.lsstcorp.org/LegalNotices/>.
22 */
23
24#ifndef LSST_CPPUTILS_PYTHON_TEMPLATEINVOKER_H
25#define LSST_CPPUTILS_PYTHON_TEMPLATEINVOKER_H
26
27#include "pybind11/pybind11.h"
28#include "pybind11/numpy.h"
29
30#include <iostream>
31
32namespace lsst { namespace cpputils { namespace python {
33
107public:
108
110 template <typename ...Types>
111 struct Tag {};
112
114 using OnErrorCallback = std::function<pybind11::object(pybind11::dtype const & dtype)>;
115
117 static pybind11::object handleErrorDefault(pybind11::dtype const & dtype) {
118 PyErr_Format(PyExc_TypeError, "dtype '%R' not supported.", dtype.ptr());
119 throw pybind11::error_already_set();
120 }
121
129 explicit TemplateInvoker(OnErrorCallback onError) : _onError(std::move(onError)) {}
130
133
155 template <typename Function, typename ...TypesToTry>
156 pybind11::object apply(
157 Function function,
158 pybind11::dtype const & dtype,
159 Tag<TypesToTry...> typesToTry
160 ) const {
161 return _apply(function, dtype, typesToTry);
162 }
163
164private:
165
166 template <typename Function>
167 pybind11::object _apply(Function & function, pybind11::dtype const & dtype, Tag<>) const {
168 return _onError(dtype);
169 }
170
171 template <typename Function, typename T, typename ...A>
172 pybind11::object _apply(Function & function, pybind11::dtype const & dtype, Tag<T, A...>) const {
173 if (pybind11::detail::npy_api::get().PyArray_EquivTypes_(dtype.ptr(),
174 pybind11::dtype::of<T>().ptr())) {
175 return pybind11::cast(function(static_cast<T>(0)));
176 }
177 return _apply(function, dtype, Tag<A...>());
178 }
179
180 OnErrorCallback _onError;
181};
182
183}}
184} // namespace lsst::cpputils::python
185
186#endif
A helper class for wrapping C++ template functions as Python functions with dtype arguments.
std::function< pybind11::object(pybind11::dtype const &dtype)> OnErrorCallback
Callback type for handling unmatched-type errors.
pybind11::object apply(Function function, pybind11::dtype const &dtype, Tag< TypesToTry... > typesToTry) const
Call and return function(static_cast<T>(0)) with the type T that matches a given NumPy dtype object.
TemplateInvoker()
Construct a TemplateInvoker that calls handleErrorDefault when no match is found.
TemplateInvoker(OnErrorCallback onError)
Construct a TemplateInvoker that calls the given object when no match is found.
static pybind11::object handleErrorDefault(pybind11::dtype const &dtype)
Callback used for handling unmatched-type errors by default.
STL namespace.
A simple tag type used to pass one or more types as a function argument.