| import functools | |
| import gc | |
| import weakref | |
| from typing import Optional, Callable, Union | |
| from weakref import WeakSet | |
| from streamlit import config | |
| from streamlit.runtime import Runtime | |
| from streamlit.runtime.scriptrunner import get_script_run_ctx, add_script_run_ctx | |
| from streamlit.web.server.server_util import make_url_path_regex |
There is sometimes a situation in which one needs to get the relative offset of a structure field, common examples of this include serialization frameworks which aid to serialize objects, vertex attributes for rendering (D3D, GL.), etc.
The most common technique for getting this information is through the offsetof
macro defined in stddef.h. Unfortunately using the macro in C++ comes with a
new set of restrictions that prevent some (subjectively valid) uses of it.
| #ifndef ACCESS_PRIVATE_CPP17 | |
| #define ACCESS_PRIVATE_CPP17 | |
| #include <functional> | |
| #define ACCESS_PRIVATE_IMPL(CLASS, NAME, CASTER, TYPE) \ | |
| namespace { \ | |
| namespace access_tag::CLASS {\ | |
| template<class T>\ | |
| struct NAME; \ |
| #ifndef BITSET_ITERATOR_HELPER_HPP | |
| #define BITSET_ITERATOR_HELPER_HPP | |
| #include <utility> | |
| #include <limits> | |
| #include <functional> | |
| #include <cstdint> | |
| template<class T> | |
| struct bitset_like_iterator_helper { |
| #include <type_traits> | |
| #include <utility> | |
| namespace Impl { | |
| // <e> <e> <e> <e> | |
| // const | |
| // volatile |
| #include <iostream> | |
| #include <stdexcept> | |
| template<typename T> | |
| struct Mock { | |
| void** mfptr = funptrs + 5; | |
| void* funptrs[15] = {{}, {}, {}, {}, {}}; | |
| // see at godbolt : https://godbolt.org/z/zMGEGs99v | |
| #include <string_view> | |
| template<auto V> | |
| constexpr static auto n() noexcept { | |
| #ifdef _MSC_VER | |
| std::string_view sv = __FUNCSIG__; | |
| auto to = sv.rfind('>')-1; | |
| for (std::size_t close = sv[to] == ')'; close > 0; ) { |
| #include <tuple> | |
| #include <limits> | |
| #define BXLX_MAXIMUM_ARG_TEMPLATE_LAMBDA 100 | |
| namespace bxlx { | |
| namespace impl { | |
| template<std::size_t> | |
| struct arg { | |
| using type = arg; |
| #include <type_traits> | |
| namespace bxlx { | |
| namespace impl { | |
| template<typename T, typename = void> | |
| struct add_long { | |
| using type = T; | |
| }; | |
| template<> |
| #include <type_traits> | |
| #include <string_view> | |
| #include <iostream> | |
| #include <atomic> | |
| #include <utility> | |
| #include <tuple> | |
| #include <cassert> | |
| template<char... Chars> | |
| struct str { |