/usr/include/pybind11/cast.h is in pybind11-dev 2.0.1-4.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 | /*
pybind11/cast.h: Partial template specializations to cast between
C++ and Python types
Copyright (c) 2016 Wenzel Jakob <wenzel.jakob@epfl.ch>
All rights reserved. Use of this source code is governed by a
BSD-style license that can be found in the LICENSE file.
*/
#pragma once
#include "pytypes.h"
#include "typeid.h"
#include "descr.h"
#include <array>
#include <limits>
NAMESPACE_BEGIN(pybind11)
NAMESPACE_BEGIN(detail)
/// Additional type information which does not fit into the PyTypeObject
struct type_info {
PyTypeObject *type;
size_t type_size;
void (*init_holder)(PyObject *, const void *);
std::vector<PyObject *(*)(PyObject *, PyTypeObject *)> implicit_conversions;
std::vector<std::pair<const std::type_info *, void *(*)(void *)>> implicit_casts;
std::vector<bool (*)(PyObject *, void *&)> *direct_conversions;
buffer_info *(*get_buffer)(PyObject *, void *) = nullptr;
void *get_buffer_data = nullptr;
/** A simple type never occurs as a (direct or indirect) parent
* of a class that makes use of multiple inheritance */
bool simple_type = true;
};
PYBIND11_NOINLINE inline internals &get_internals() {
static internals *internals_ptr = nullptr;
if (internals_ptr)
return *internals_ptr;
handle builtins(PyEval_GetBuiltins());
const char *id = PYBIND11_INTERNALS_ID;
if (builtins.contains(id) && isinstance<capsule>(builtins[id])) {
internals_ptr = capsule(builtins[id]);
} else {
internals_ptr = new internals();
#if defined(WITH_THREAD)
PyEval_InitThreads();
PyThreadState *tstate = PyThreadState_Get();
internals_ptr->tstate = PyThread_create_key();
PyThread_set_key_value(internals_ptr->tstate, tstate);
internals_ptr->istate = tstate->interp;
#endif
builtins[id] = capsule(internals_ptr);
internals_ptr->registered_exception_translators.push_front(
[](std::exception_ptr p) -> void {
try {
if (p) std::rethrow_exception(p);
} catch (error_already_set &e) { e.restore(); return;
} catch (const builtin_exception &e) { e.set_error(); return;
} catch (const std::bad_alloc &e) { PyErr_SetString(PyExc_MemoryError, e.what()); return;
} catch (const std::domain_error &e) { PyErr_SetString(PyExc_ValueError, e.what()); return;
} catch (const std::invalid_argument &e) { PyErr_SetString(PyExc_ValueError, e.what()); return;
} catch (const std::length_error &e) { PyErr_SetString(PyExc_ValueError, e.what()); return;
} catch (const std::out_of_range &e) { PyErr_SetString(PyExc_IndexError, e.what()); return;
} catch (const std::range_error &e) { PyErr_SetString(PyExc_ValueError, e.what()); return;
} catch (const std::exception &e) { PyErr_SetString(PyExc_RuntimeError, e.what()); return;
} catch (...) {
PyErr_SetString(PyExc_RuntimeError, "Caught an unknown exception!");
return;
}
}
);
}
return *internals_ptr;
}
PYBIND11_NOINLINE inline detail::type_info* get_type_info(PyTypeObject *type) {
auto const &type_dict = get_internals().registered_types_py;
do {
auto it = type_dict.find(type);
if (it != type_dict.end())
return (detail::type_info *) it->second;
type = type->tp_base;
if (!type)
return nullptr;
} while (true);
}
PYBIND11_NOINLINE inline detail::type_info *get_type_info(const std::type_info &tp,
bool throw_if_missing = false) {
auto &types = get_internals().registered_types_cpp;
auto it = types.find(std::type_index(tp));
if (it != types.end())
return (detail::type_info *) it->second;
if (throw_if_missing) {
std::string tname = tp.name();
detail::clean_type_id(tname);
pybind11_fail("pybind11::detail::get_type_info: unable to find type info for \"" + tname + "\"");
}
return nullptr;
}
PYBIND11_NOINLINE inline handle get_type_handle(const std::type_info &tp, bool throw_if_missing) {
detail::type_info *type_info = get_type_info(tp, throw_if_missing);
return handle(type_info ? ((PyObject *) type_info->type) : nullptr);
}
PYBIND11_NOINLINE inline bool isinstance_generic(handle obj, const std::type_info &tp) {
handle type = detail::get_type_handle(tp, false);
if (!type)
return false;
return isinstance(obj, type);
}
PYBIND11_NOINLINE inline std::string error_string() {
if (!PyErr_Occurred()) {
PyErr_SetString(PyExc_RuntimeError, "Unknown internal error occurred");
return "Unknown internal error occurred";
}
error_scope scope; // Preserve error state
std::string errorString;
if (scope.type) {
errorString += handle(scope.type).attr("__name__").cast<std::string>();
errorString += ": ";
}
if (scope.value)
errorString += (std::string) str(scope.value);
PyErr_NormalizeException(&scope.type, &scope.value, &scope.trace);
#if PY_MAJOR_VERSION >= 3
if (scope.trace != nullptr)
PyException_SetTraceback(scope.value, scope.trace);
#endif
#if !defined(PYPY_VERSION)
if (scope.trace) {
PyTracebackObject *trace = (PyTracebackObject *) scope.trace;
/* Get the deepest trace possible */
while (trace->tb_next)
trace = trace->tb_next;
PyFrameObject *frame = trace->tb_frame;
errorString += "\n\nAt:\n";
while (frame) {
int lineno = PyFrame_GetLineNumber(frame);
errorString +=
" " + handle(frame->f_code->co_filename).cast<std::string>() +
"(" + std::to_string(lineno) + "): " +
handle(frame->f_code->co_name).cast<std::string>() + "\n";
frame = frame->f_back;
}
trace = trace->tb_next;
}
#endif
return errorString;
}
PYBIND11_NOINLINE inline handle get_object_handle(const void *ptr, const detail::type_info *type ) {
auto &instances = get_internals().registered_instances;
auto range = instances.equal_range(ptr);
for (auto it = range.first; it != range.second; ++it) {
auto instance_type = detail::get_type_info(Py_TYPE(it->second));
if (instance_type && instance_type == type)
return handle((PyObject *) it->second);
}
return handle();
}
inline PyThreadState *get_thread_state_unchecked() {
#if defined(PYPY_VERSION)
return PyThreadState_GET();
#elif PY_VERSION_HEX < 0x03000000
return _PyThreadState_Current;
#elif PY_VERSION_HEX < 0x03050000
return (PyThreadState*) _Py_atomic_load_relaxed(&_PyThreadState_Current);
#elif PY_VERSION_HEX < 0x03050200
return (PyThreadState*) _PyThreadState_Current.value;
#else
return _PyThreadState_UncheckedGet();
#endif
}
// Forward declaration
inline void keep_alive_impl(handle nurse, handle patient);
class type_caster_generic {
public:
PYBIND11_NOINLINE type_caster_generic(const std::type_info &type_info)
: typeinfo(get_type_info(type_info)) { }
PYBIND11_NOINLINE bool load(handle src, bool convert) {
if (!src)
return false;
return load(src, convert, Py_TYPE(src.ptr()));
}
bool load(handle src, bool convert, PyTypeObject *tobj) {
if (!src || !typeinfo)
return false;
if (src.is_none()) {
value = nullptr;
return true;
}
if (typeinfo->simple_type) { /* Case 1: no multiple inheritance etc. involved */
/* Check if we can safely perform a reinterpret-style cast */
if (PyType_IsSubtype(tobj, typeinfo->type)) {
value = reinterpret_cast<instance<void> *>(src.ptr())->value;
return true;
}
} else { /* Case 2: multiple inheritance */
/* Check if we can safely perform a reinterpret-style cast */
if (tobj == typeinfo->type) {
value = reinterpret_cast<instance<void> *>(src.ptr())->value;
return true;
}
/* If this is a python class, also check the parents recursively */
auto const &type_dict = get_internals().registered_types_py;
bool new_style_class = PyType_Check((PyObject *) tobj);
if (type_dict.find(tobj) == type_dict.end() && new_style_class && tobj->tp_bases) {
auto parents = reinterpret_borrow<tuple>(tobj->tp_bases);
for (handle parent : parents) {
bool result = load(src, convert, (PyTypeObject *) parent.ptr());
if (result)
return true;
}
}
/* Try implicit casts */
for (auto &cast : typeinfo->implicit_casts) {
type_caster_generic sub_caster(*cast.first);
if (sub_caster.load(src, convert)) {
value = cast.second(sub_caster.value);
return true;
}
}
}
/* Perform an implicit conversion */
if (convert) {
for (auto &converter : typeinfo->implicit_conversions) {
temp = reinterpret_steal<object>(converter(src.ptr(), typeinfo->type));
if (load(temp, false))
return true;
}
for (auto &converter : *typeinfo->direct_conversions) {
if (converter(src.ptr(), value))
return true;
}
}
return false;
}
PYBIND11_NOINLINE static handle cast(const void *_src, return_value_policy policy, handle parent,
const std::type_info *type_info,
const std::type_info *type_info_backup,
void *(*copy_constructor)(const void *),
void *(*move_constructor)(const void *),
const void *existing_holder = nullptr) {
void *src = const_cast<void *>(_src);
if (src == nullptr)
return none().inc_ref();
auto &internals = get_internals();
auto it = internals.registered_types_cpp.find(std::type_index(*type_info));
if (it == internals.registered_types_cpp.end()) {
type_info = type_info_backup;
it = internals.registered_types_cpp.find(std::type_index(*type_info));
}
if (it == internals.registered_types_cpp.end()) {
std::string tname = type_info->name();
detail::clean_type_id(tname);
std::string msg = "Unregistered type : " + tname;
PyErr_SetString(PyExc_TypeError, msg.c_str());
return handle();
}
auto tinfo = (const detail::type_info *) it->second;
auto it_instances = internals.registered_instances.equal_range(src);
for (auto it_i = it_instances.first; it_i != it_instances.second; ++it_i) {
auto instance_type = detail::get_type_info(Py_TYPE(it_i->second));
if (instance_type && instance_type == tinfo)
return handle((PyObject *) it_i->second).inc_ref();
}
auto inst = reinterpret_steal<object>(PyType_GenericAlloc(tinfo->type, 0));
auto wrapper = (instance<void> *) inst.ptr();
wrapper->value = nullptr;
wrapper->owned = false;
switch (policy) {
case return_value_policy::automatic:
case return_value_policy::take_ownership:
wrapper->value = src;
wrapper->owned = true;
break;
case return_value_policy::automatic_reference:
case return_value_policy::reference:
wrapper->value = src;
wrapper->owned = false;
break;
case return_value_policy::copy:
if (copy_constructor)
wrapper->value = copy_constructor(src);
else
throw cast_error("return_value_policy = copy, but the "
"object is non-copyable!");
wrapper->owned = true;
break;
case return_value_policy::move:
if (move_constructor)
wrapper->value = move_constructor(src);
else if (copy_constructor)
wrapper->value = copy_constructor(src);
else
throw cast_error("return_value_policy = move, but the "
"object is neither movable nor copyable!");
wrapper->owned = true;
break;
case return_value_policy::reference_internal:
wrapper->value = src;
wrapper->owned = false;
detail::keep_alive_impl(inst, parent);
break;
default:
throw cast_error("unhandled return_value_policy: should not happen!");
}
tinfo->init_holder(inst.ptr(), existing_holder);
internals.registered_instances.emplace(wrapper->value, inst.ptr());
return inst.release();
}
protected:
const type_info *typeinfo = nullptr;
void *value = nullptr;
object temp;
};
/* Determine suitable casting operator */
template <typename T>
using cast_op_type = typename std::conditional<std::is_pointer<typename std::remove_reference<T>::type>::value,
typename std::add_pointer<intrinsic_t<T>>::type,
typename std::add_lvalue_reference<intrinsic_t<T>>::type>::type;
// std::is_copy_constructible isn't quite enough: it lets std::vector<T> (and similar) through when
// T is non-copyable, but code containing such a copy constructor fails to actually compile.
template <typename T, typename SFINAE = void> struct is_copy_constructible : std::is_copy_constructible<T> {};
// Specialization for types that appear to be copy constructible but also look like stl containers
// (we specifically check for: has `value_type` and `reference` with `reference = value_type&`): if
// so, copy constructability depends on whether the value_type is copy constructible.
template <typename Container> struct is_copy_constructible<Container, enable_if_t<
std::is_copy_constructible<Container>::value &&
std::is_same<typename Container::value_type &, typename Container::reference>::value
>> : std::is_copy_constructible<typename Container::value_type> {};
/// Generic type caster for objects stored on the heap
template <typename type> class type_caster_base : public type_caster_generic {
using itype = intrinsic_t<type>;
public:
static PYBIND11_DESCR name() { return type_descr(_<type>()); }
type_caster_base() : type_caster_base(typeid(type)) { }
explicit type_caster_base(const std::type_info &info) : type_caster_generic(info) { }
static handle cast(const itype &src, return_value_policy policy, handle parent) {
if (policy == return_value_policy::automatic || policy == return_value_policy::automatic_reference)
policy = return_value_policy::copy;
return cast(&src, policy, parent);
}
static handle cast(itype &&src, return_value_policy, handle parent) {
return cast(&src, return_value_policy::move, parent);
}
static handle cast(const itype *src, return_value_policy policy, handle parent) {
return type_caster_generic::cast(
src, policy, parent, src ? &typeid(*src) : nullptr, &typeid(type),
make_copy_constructor(src), make_move_constructor(src));
}
template <typename T> using cast_op_type = pybind11::detail::cast_op_type<T>;
operator itype*() { return (type *) value; }
operator itype&() { if (!value) throw reference_cast_error(); return *((itype *) value); }
protected:
typedef void *(*Constructor)(const void *stream);
#if !defined(_MSC_VER)
/* Only enabled when the types are {copy,move}-constructible *and* when the type
does not have a private operator new implementaton. */
template <typename T = type, typename = enable_if_t<is_copy_constructible<T>::value>> static auto make_copy_constructor(const T *value) -> decltype(new T(*value), Constructor(nullptr)) {
return [](const void *arg) -> void * { return new T(*((const T *) arg)); }; }
template <typename T = type> static auto make_move_constructor(const T *value) -> decltype(new T(std::move(*((T *) value))), Constructor(nullptr)) {
return [](const void *arg) -> void * { return (void *) new T(std::move(*((T *) arg))); }; }
#else
/* Visual Studio 2015's SFINAE implementation doesn't yet handle the above robustly in all situations.
Use a workaround that only tests for constructibility for now. */
template <typename T = type, typename = enable_if_t<is_copy_constructible<T>::value>>
static Constructor make_copy_constructor(const T *value) {
return [](const void *arg) -> void * { return new T(*((const T *)arg)); }; }
template <typename T = type, typename = enable_if_t<std::is_move_constructible<T>::value>>
static Constructor make_move_constructor(const T *value) {
return [](const void *arg) -> void * { return (void *) new T(std::move(*((T *)arg))); }; }
#endif
static Constructor make_copy_constructor(...) { return nullptr; }
static Constructor make_move_constructor(...) { return nullptr; }
};
template <typename type, typename SFINAE = void> class type_caster : public type_caster_base<type> { };
template <typename type> using make_caster = type_caster<intrinsic_t<type>>;
// Shortcut for calling a caster's `cast_op_type` cast operator for casting a type_caster to a T
template <typename T> typename make_caster<T>::template cast_op_type<T> cast_op(make_caster<T> &caster) {
return caster.operator typename make_caster<T>::template cast_op_type<T>();
}
template <typename T> typename make_caster<T>::template cast_op_type<T> cast_op(make_caster<T> &&caster) {
return cast_op<T>(caster);
}
template <typename type> class type_caster<std::reference_wrapper<type>> : public type_caster_base<type> {
public:
static handle cast(const std::reference_wrapper<type> &src, return_value_policy policy, handle parent) {
return type_caster_base<type>::cast(&src.get(), policy, parent);
}
template <typename T> using cast_op_type = std::reference_wrapper<type>;
operator std::reference_wrapper<type>() { return std::ref(*((type *) this->value)); }
};
#define PYBIND11_TYPE_CASTER(type, py_name) \
protected: \
type value; \
public: \
static PYBIND11_DESCR name() { return type_descr(py_name); } \
static handle cast(const type *src, return_value_policy policy, handle parent) { \
return cast(*src, policy, parent); \
} \
operator type*() { return &value; } \
operator type&() { return value; } \
template <typename _T> using cast_op_type = pybind11::detail::cast_op_type<_T>
template <typename T>
struct type_caster<T, enable_if_t<std::is_arithmetic<T>::value>> {
typedef typename std::conditional<sizeof(T) <= sizeof(long), long, long long>::type _py_type_0;
typedef typename std::conditional<std::is_signed<T>::value, _py_type_0, typename std::make_unsigned<_py_type_0>::type>::type _py_type_1;
typedef typename std::conditional<std::is_floating_point<T>::value, double, _py_type_1>::type py_type;
public:
bool load(handle src, bool) {
py_type py_value;
if (!src) {
return false;
} if (std::is_floating_point<T>::value) {
py_value = (py_type) PyFloat_AsDouble(src.ptr());
} else if (sizeof(T) <= sizeof(long)) {
if (PyFloat_Check(src.ptr()))
return false;
if (std::is_signed<T>::value)
py_value = (py_type) PyLong_AsLong(src.ptr());
else
py_value = (py_type) PyLong_AsUnsignedLong(src.ptr());
} else {
if (PyFloat_Check(src.ptr()))
return false;
if (std::is_signed<T>::value)
py_value = (py_type) PYBIND11_LONG_AS_LONGLONG(src.ptr());
else
py_value = (py_type) PYBIND11_LONG_AS_UNSIGNED_LONGLONG(src.ptr());
}
if ((py_value == (py_type) -1 && PyErr_Occurred()) ||
(std::is_integral<T>::value && sizeof(py_type) != sizeof(T) &&
(py_value < (py_type) std::numeric_limits<T>::min() ||
py_value > (py_type) std::numeric_limits<T>::max()))) {
#if PY_VERSION_HEX < 0x03000000
bool type_error = PyErr_ExceptionMatches(PyExc_SystemError);
#else
bool type_error = PyErr_ExceptionMatches(PyExc_TypeError);
#endif
PyErr_Clear();
if (type_error && PyNumber_Check(src.ptr())) {
auto tmp = reinterpret_borrow<object>(std::is_floating_point<T>::value
? PyNumber_Float(src.ptr())
: PyNumber_Long(src.ptr()));
PyErr_Clear();
return load(tmp, false);
}
return false;
}
value = (T) py_value;
return true;
}
static handle cast(T src, return_value_policy /* policy */, handle /* parent */) {
if (std::is_floating_point<T>::value) {
return PyFloat_FromDouble((double) src);
} else if (sizeof(T) <= sizeof(long)) {
if (std::is_signed<T>::value)
return PyLong_FromLong((long) src);
else
return PyLong_FromUnsignedLong((unsigned long) src);
} else {
if (std::is_signed<T>::value)
return PyLong_FromLongLong((long long) src);
else
return PyLong_FromUnsignedLongLong((unsigned long long) src);
}
}
PYBIND11_TYPE_CASTER(T, _<std::is_integral<T>::value>("int", "float"));
};
template<typename T> struct void_caster {
public:
bool load(handle, bool) { return false; }
static handle cast(T, return_value_policy /* policy */, handle /* parent */) {
return none().inc_ref();
}
PYBIND11_TYPE_CASTER(T, _("None"));
};
template <> class type_caster<void_type> : public void_caster<void_type> {};
template <> class type_caster<void> : public type_caster<void_type> {
public:
using type_caster<void_type>::cast;
bool load(handle h, bool) {
if (!h) {
return false;
} else if (h.is_none()) {
value = nullptr;
return true;
}
/* Check if this is a capsule */
if (isinstance<capsule>(h)) {
value = reinterpret_borrow<capsule>(h);
return true;
}
/* Check if this is a C++ type */
if (get_type_info((PyTypeObject *) h.get_type().ptr())) {
value = ((instance<void> *) h.ptr())->value;
return true;
}
/* Fail */
return false;
}
static handle cast(const void *ptr, return_value_policy /* policy */, handle /* parent */) {
if (ptr)
return capsule(ptr).release();
else
return none().inc_ref();
}
template <typename T> using cast_op_type = void*&;
operator void *&() { return value; }
static PYBIND11_DESCR name() { return type_descr(_("capsule")); }
private:
void *value = nullptr;
};
template <> class type_caster<std::nullptr_t> : public type_caster<void_type> { };
template <> class type_caster<bool> {
public:
bool load(handle src, bool) {
if (!src) return false;
else if (src.ptr() == Py_True) { value = true; return true; }
else if (src.ptr() == Py_False) { value = false; return true; }
else return false;
}
static handle cast(bool src, return_value_policy /* policy */, handle /* parent */) {
return handle(src ? Py_True : Py_False).inc_ref();
}
PYBIND11_TYPE_CASTER(bool, _("bool"));
};
template <> class type_caster<std::string> {
public:
bool load(handle src, bool) {
object temp;
handle load_src = src;
if (!src) {
return false;
} else if (PyUnicode_Check(load_src.ptr())) {
temp = reinterpret_steal<object>(PyUnicode_AsUTF8String(load_src.ptr()));
if (!temp) { PyErr_Clear(); return false; } // UnicodeEncodeError
load_src = temp;
}
char *buffer;
ssize_t length;
int err = PYBIND11_BYTES_AS_STRING_AND_SIZE(load_src.ptr(), &buffer, &length);
if (err == -1) { PyErr_Clear(); return false; } // TypeError
value = std::string(buffer, (size_t) length);
success = true;
return true;
}
static handle cast(const std::string &src, return_value_policy /* policy */, handle /* parent */) {
return PyUnicode_FromStringAndSize(src.c_str(), (ssize_t) src.length());
}
PYBIND11_TYPE_CASTER(std::string, _(PYBIND11_STRING_NAME));
protected:
bool success = false;
};
template <typename type, typename deleter> class type_caster<std::unique_ptr<type, deleter>> {
public:
static handle cast(std::unique_ptr<type, deleter> &&src, return_value_policy policy, handle parent) {
handle result = type_caster_base<type>::cast(src.get(), policy, parent);
if (result)
src.release();
return result;
}
static PYBIND11_DESCR name() { return type_caster_base<type>::name(); }
};
template <> class type_caster<std::wstring> {
public:
bool load(handle src, bool) {
object temp;
handle load_src = src;
if (!src) {
return false;
} else if (!PyUnicode_Check(load_src.ptr())) {
temp = reinterpret_steal<object>(PyUnicode_FromObject(load_src.ptr()));
if (!temp) { PyErr_Clear(); return false; }
load_src = temp;
}
wchar_t *buffer = nullptr;
ssize_t length = -1;
#if PY_MAJOR_VERSION >= 3
buffer = PyUnicode_AsWideCharString(load_src.ptr(), &length);
#else
temp = reinterpret_steal<object>(PyUnicode_AsEncodedString(
load_src.ptr(), sizeof(wchar_t) == sizeof(short)
? "utf16" : "utf32", nullptr));
if (temp) {
int err = PYBIND11_BYTES_AS_STRING_AND_SIZE(temp.ptr(), (char **) &buffer, &length);
if (err == -1) { buffer = nullptr; } // TypeError
length = length / (ssize_t) sizeof(wchar_t) - 1; ++buffer; // Skip BOM
}
#endif
if (!buffer) { PyErr_Clear(); return false; }
value = std::wstring(buffer, (size_t) length);
success = true;
return true;
}
static handle cast(const std::wstring &src, return_value_policy /* policy */, handle /* parent */) {
return PyUnicode_FromWideChar(src.c_str(), (ssize_t) src.length());
}
PYBIND11_TYPE_CASTER(std::wstring, _(PYBIND11_STRING_NAME));
protected:
bool success = false;
};
template <> class type_caster<char> : public type_caster<std::string> {
public:
bool load(handle src, bool convert) {
if (src.is_none()) return true;
return type_caster<std::string>::load(src, convert);
}
static handle cast(const char *src, return_value_policy /* policy */, handle /* parent */) {
if (src == nullptr) return none().inc_ref();
return PyUnicode_FromString(src);
}
static handle cast(char src, return_value_policy /* policy */, handle /* parent */) {
char str[2] = { src, '\0' };
return PyUnicode_DecodeLatin1(str, 1, nullptr);
}
operator char*() { return success ? (char *) value.c_str() : nullptr; }
operator char&() { return value[0]; }
static PYBIND11_DESCR name() { return type_descr(_(PYBIND11_STRING_NAME)); }
};
template <> class type_caster<wchar_t> : public type_caster<std::wstring> {
public:
bool load(handle src, bool convert) {
if (src.is_none()) return true;
return type_caster<std::wstring>::load(src, convert);
}
static handle cast(const wchar_t *src, return_value_policy /* policy */, handle /* parent */) {
if (src == nullptr) return none().inc_ref();
return PyUnicode_FromWideChar(src, (ssize_t) wcslen(src));
}
static handle cast(wchar_t src, return_value_policy /* policy */, handle /* parent */) {
wchar_t wstr[2] = { src, L'\0' };
return PyUnicode_FromWideChar(wstr, 1);
}
operator wchar_t*() { return success ? (wchar_t *) value.c_str() : nullptr; }
operator wchar_t&() { return value[0]; }
static PYBIND11_DESCR name() { return type_descr(_(PYBIND11_STRING_NAME)); }
};
template <typename T1, typename T2> class type_caster<std::pair<T1, T2>> {
typedef std::pair<T1, T2> type;
public:
bool load(handle src, bool convert) {
if (!isinstance<sequence>(src))
return false;
const auto seq = reinterpret_borrow<sequence>(src);
if (seq.size() != 2)
return false;
return first.load(seq[0], convert) && second.load(seq[1], convert);
}
static handle cast(const type &src, return_value_policy policy, handle parent) {
auto o1 = reinterpret_steal<object>(make_caster<T1>::cast(src.first, policy, parent));
auto o2 = reinterpret_steal<object>(make_caster<T2>::cast(src.second, policy, parent));
if (!o1 || !o2)
return handle();
tuple result(2);
PyTuple_SET_ITEM(result.ptr(), 0, o1.release().ptr());
PyTuple_SET_ITEM(result.ptr(), 1, o2.release().ptr());
return result.release();
}
static PYBIND11_DESCR name() {
return type_descr(
_("Tuple[") + make_caster<T1>::name() + _(", ") + make_caster<T2>::name() + _("]")
);
}
template <typename T> using cast_op_type = type;
operator type() {
return type(cast_op<T1>(first), cast_op<T2>(second));
}
protected:
make_caster<T1> first;
make_caster<T2> second;
};
template <typename... Tuple> class type_caster<std::tuple<Tuple...>> {
using type = std::tuple<Tuple...>;
using indices = make_index_sequence<sizeof...(Tuple)>;
static constexpr auto size = sizeof...(Tuple);
public:
bool load(handle src, bool convert) {
if (!isinstance<sequence>(src))
return false;
const auto seq = reinterpret_borrow<sequence>(src);
if (seq.size() != size)
return false;
return load_impl(seq, convert, indices{});
}
static handle cast(const type &src, return_value_policy policy, handle parent) {
return cast_impl(src, policy, parent, indices{});
}
static PYBIND11_DESCR name() {
return type_descr(_("Tuple[") + detail::concat(make_caster<Tuple>::name()...) + _("]"));
}
template <typename T> using cast_op_type = type;
operator type() { return implicit_cast(indices{}); }
protected:
template <size_t... Is>
type implicit_cast(index_sequence<Is...>) { return type(cast_op<Tuple>(std::get<Is>(value))...); }
static constexpr bool load_impl(const sequence &, bool, index_sequence<>) { return true; }
template <size_t... Is>
bool load_impl(const sequence &seq, bool convert, index_sequence<Is...>) {
for (bool r : {std::get<Is>(value).load(seq[Is], convert)...})
if (!r)
return false;
return true;
}
static handle cast_impl(const type &, return_value_policy, handle,
index_sequence<>) { return tuple().release(); }
/* Implementation: Convert a C++ tuple into a Python tuple */
template <size_t... Is>
static handle cast_impl(const type &src, return_value_policy policy, handle parent, index_sequence<Is...>) {
std::array<object, size> entries {{
reinterpret_steal<object>(make_caster<Tuple>::cast(std::get<Is>(src), policy, parent))...
}};
for (const auto &entry: entries)
if (!entry)
return handle();
tuple result(size);
int counter = 0;
for (auto & entry: entries)
PyTuple_SET_ITEM(result.ptr(), counter++, entry.release().ptr());
return result.release();
}
std::tuple<make_caster<Tuple>...> value;
};
/// Type caster for holder types like std::shared_ptr, etc.
template <typename type, typename holder_type> class type_caster_holder : public type_caster_base<type> {
public:
using base = type_caster_base<type>;
using base::base;
using base::cast;
using base::typeinfo;
using base::value;
using base::temp;
PYBIND11_NOINLINE bool load(handle src, bool convert) {
return load(src, convert, Py_TYPE(src.ptr()));
}
bool load(handle src, bool convert, PyTypeObject *tobj) {
if (!src || !typeinfo)
return false;
if (src.is_none()) {
value = nullptr;
return true;
}
if (typeinfo->simple_type) { /* Case 1: no multiple inheritance etc. involved */
/* Check if we can safely perform a reinterpret-style cast */
if (PyType_IsSubtype(tobj, typeinfo->type))
return load_value_and_holder(src);
} else { /* Case 2: multiple inheritance */
/* Check if we can safely perform a reinterpret-style cast */
if (tobj == typeinfo->type)
return load_value_and_holder(src);
/* If this is a python class, also check the parents recursively */
auto const &type_dict = get_internals().registered_types_py;
bool new_style_class = PyType_Check((PyObject *) tobj);
if (type_dict.find(tobj) == type_dict.end() && new_style_class && tobj->tp_bases) {
auto parents = reinterpret_borrow<tuple>(tobj->tp_bases);
for (handle parent : parents) {
bool result = load(src, convert, (PyTypeObject *) parent.ptr());
if (result)
return true;
}
}
if (try_implicit_casts(src, convert))
return true;
}
if (convert) {
for (auto &converter : typeinfo->implicit_conversions) {
temp = reinterpret_steal<object>(converter(src.ptr(), typeinfo->type));
if (load(temp, false))
return true;
}
}
return false;
}
bool load_value_and_holder(handle src) {
auto inst = (instance<type, holder_type> *) src.ptr();
value = (void *) inst->value;
if (inst->holder_constructed) {
holder = inst->holder;
return true;
} else {
throw cast_error("Unable to cast from non-held to held instance (T& to Holder<T>) "
#if defined(NDEBUG)
"(compile in debug mode for type information)");
#else
"of type '" + type_id<holder_type>() + "''");
#endif
}
}
template <typename T = holder_type, detail::enable_if_t<!std::is_constructible<T, const T &, type*>::value, int> = 0>
bool try_implicit_casts(handle, bool) { return false; }
template <typename T = holder_type, detail::enable_if_t<std::is_constructible<T, const T &, type*>::value, int> = 0>
bool try_implicit_casts(handle src, bool convert) {
for (auto &cast : typeinfo->implicit_casts) {
type_caster_holder sub_caster(*cast.first);
if (sub_caster.load(src, convert)) {
value = cast.second(sub_caster.value);
holder = holder_type(sub_caster.holder, (type *) value);
return true;
}
}
return false;
}
explicit operator type*() { return this->value; }
explicit operator type&() { return *(this->value); }
explicit operator holder_type*() { return &holder; }
// Workaround for Intel compiler bug
// see pybind11 issue 94
#if defined(__ICC) || defined(__INTEL_COMPILER)
operator holder_type&() { return holder; }
#else
explicit operator holder_type&() { return holder; }
#endif
static handle cast(const holder_type &src, return_value_policy, handle) {
return type_caster_generic::cast(
src.get(), return_value_policy::take_ownership, handle(),
src.get() ? &typeid(*src.get()) : nullptr, &typeid(type),
nullptr, nullptr, &src);
}
protected:
holder_type holder;
};
/// Specialize for the common std::shared_ptr, so users don't need to
template <typename T>
class type_caster<std::shared_ptr<T>> : public type_caster_holder<T, std::shared_ptr<T>> { };
template <typename T, bool Value = false> struct always_construct_holder { static constexpr bool value = Value; };
/// Create a specialization for custom holder types (silently ignores std::shared_ptr)
#define PYBIND11_DECLARE_HOLDER_TYPE(type, holder_type, ...) \
namespace pybind11 { namespace detail { \
template <typename type> \
struct always_construct_holder<holder_type> : always_construct_holder<void, ##__VA_ARGS__> { }; \
template <typename type> \
class type_caster<holder_type, enable_if_t<!is_shared_ptr<holder_type>::value>> \
: public type_caster_holder<type, holder_type> { }; \
}}
// PYBIND11_DECLARE_HOLDER_TYPE holder types:
template <typename base, typename holder> struct is_holder_type :
std::is_base_of<detail::type_caster_holder<base, holder>, detail::type_caster<holder>> {};
// Specialization for always-supported unique_ptr holders:
template <typename base, typename deleter> struct is_holder_type<base, std::unique_ptr<base, deleter>> :
std::true_type {};
template <typename T> struct handle_type_name { static PYBIND11_DESCR name() { return _<T>(); } };
template <> struct handle_type_name<bytes> { static PYBIND11_DESCR name() { return _(PYBIND11_BYTES_NAME); } };
template <> struct handle_type_name<args> { static PYBIND11_DESCR name() { return _("*args"); } };
template <> struct handle_type_name<kwargs> { static PYBIND11_DESCR name() { return _("**kwargs"); } };
template <typename type>
struct pyobject_caster {
template <typename T = type, enable_if_t<std::is_same<T, handle>::value, int> = 0>
bool load(handle src, bool /* convert */) { value = src; return static_cast<bool>(value); }
template <typename T = type, enable_if_t<std::is_base_of<object, T>::value, int> = 0>
bool load(handle src, bool /* convert */) {
if (!isinstance<type>(src))
return false;
value = reinterpret_borrow<type>(src);
return true;
}
static handle cast(const handle &src, return_value_policy /* policy */, handle /* parent */) {
return src.inc_ref();
}
PYBIND11_TYPE_CASTER(type, handle_type_name<type>::name());
};
template <typename T>
class type_caster<T, enable_if_t<is_pyobject<T>::value>> : public pyobject_caster<T> { };
// Our conditions for enabling moving are quite restrictive:
// At compile time:
// - T needs to be a non-const, non-pointer, non-reference type
// - type_caster<T>::operator T&() must exist
// - the type must be move constructible (obviously)
// At run-time:
// - if the type is non-copy-constructible, the object must be the sole owner of the type (i.e. it
// must have ref_count() == 1)h
// If any of the above are not satisfied, we fall back to copying.
template <typename T> using move_is_plain_type = none_of<
std::is_void<T>, std::is_pointer<T>, std::is_reference<T>, std::is_const<T>
>;
template <typename T, typename SFINAE = void> struct move_always : std::false_type {};
template <typename T> struct move_always<T, enable_if_t<all_of<
move_is_plain_type<T>,
negation<std::is_copy_constructible<T>>,
std::is_move_constructible<T>,
std::is_same<decltype(std::declval<make_caster<T>>().operator T&()), T&>
>::value>> : std::true_type {};
template <typename T, typename SFINAE = void> struct move_if_unreferenced : std::false_type {};
template <typename T> struct move_if_unreferenced<T, enable_if_t<all_of<
move_is_plain_type<T>,
negation<move_always<T>>,
std::is_move_constructible<T>,
std::is_same<decltype(std::declval<make_caster<T>>().operator T&()), T&>
>::value>> : std::true_type {};
template <typename T> using move_never = none_of<move_always<T>, move_if_unreferenced<T>>;
// Detect whether returning a `type` from a cast on type's type_caster is going to result in a
// reference or pointer to a local variable of the type_caster. Basically, only
// non-reference/pointer `type`s and reference/pointers from a type_caster_generic are safe;
// everything else returns a reference/pointer to a local variable.
template <typename type> using cast_is_temporary_value_reference = bool_constant<
(std::is_reference<type>::value || std::is_pointer<type>::value) &&
!std::is_base_of<type_caster_generic, make_caster<type>>::value
>;
// Basic python -> C++ casting; throws if casting fails
template <typename T, typename SFINAE> type_caster<T, SFINAE> &load_type(type_caster<T, SFINAE> &conv, const handle &handle) {
if (!conv.load(handle, true)) {
#if defined(NDEBUG)
throw cast_error("Unable to cast Python instance to C++ type (compile in debug mode for details)");
#else
throw cast_error("Unable to cast Python instance of type " +
(std::string) str(handle.get_type()) + " to C++ type '" + type_id<T>() + "''");
#endif
}
return conv;
}
// Wrapper around the above that also constructs and returns a type_caster
template <typename T> make_caster<T> load_type(const handle &handle) {
make_caster<T> conv;
load_type(conv, handle);
return conv;
}
NAMESPACE_END(detail)
// pytype -> C++ type
template <typename T, detail::enable_if_t<!detail::is_pyobject<T>::value, int> = 0>
T cast(const handle &handle) {
using namespace detail;
static_assert(!cast_is_temporary_value_reference<T>::value,
"Unable to cast type to reference: value is local to type caster");
return cast_op<T>(load_type<T>(handle));
}
// pytype -> pytype (calls converting constructor)
template <typename T, detail::enable_if_t<detail::is_pyobject<T>::value, int> = 0>
T cast(const handle &handle) { return T(reinterpret_borrow<object>(handle)); }
// C++ type -> py::object
template <typename T, detail::enable_if_t<!detail::is_pyobject<T>::value, int> = 0>
object cast(const T &value, return_value_policy policy = return_value_policy::automatic_reference,
handle parent = handle()) {
if (policy == return_value_policy::automatic)
policy = std::is_pointer<T>::value ? return_value_policy::take_ownership : return_value_policy::copy;
else if (policy == return_value_policy::automatic_reference)
policy = std::is_pointer<T>::value ? return_value_policy::reference : return_value_policy::copy;
return reinterpret_steal<object>(detail::make_caster<T>::cast(value, policy, parent));
}
template <typename T> T handle::cast() const { return pybind11::cast<T>(*this); }
template <> inline void handle::cast() const { return; }
template <typename T>
detail::enable_if_t<!detail::move_never<T>::value, T> move(object &&obj) {
if (obj.ref_count() > 1)
#if defined(NDEBUG)
throw cast_error("Unable to cast Python instance to C++ rvalue: instance has multiple references"
" (compile in debug mode for details)");
#else
throw cast_error("Unable to move from Python " + (std::string) str(obj.get_type()) +
" instance to C++ " + type_id<T>() + " instance: instance has multiple references");
#endif
// Move into a temporary and return that, because the reference may be a local value of `conv`
T ret = std::move(detail::load_type<T>(obj).operator T&());
return ret;
}
// Calling cast() on an rvalue calls pybind::cast with the object rvalue, which does:
// - If we have to move (because T has no copy constructor), do it. This will fail if the moved
// object has multiple references, but trying to copy will fail to compile.
// - If both movable and copyable, check ref count: if 1, move; otherwise copy
// - Otherwise (not movable), copy.
template <typename T> detail::enable_if_t<detail::move_always<T>::value, T> cast(object &&object) {
return move<T>(std::move(object));
}
template <typename T> detail::enable_if_t<detail::move_if_unreferenced<T>::value, T> cast(object &&object) {
if (object.ref_count() > 1)
return cast<T>(object);
else
return move<T>(std::move(object));
}
template <typename T> detail::enable_if_t<detail::move_never<T>::value, T> cast(object &&object) {
return cast<T>(object);
}
template <typename T> T object::cast() const & { return pybind11::cast<T>(*this); }
template <typename T> T object::cast() && { return pybind11::cast<T>(std::move(*this)); }
template <> inline void object::cast() const & { return; }
template <> inline void object::cast() && { return; }
NAMESPACE_BEGIN(detail)
// Declared in pytypes.h:
template <typename T, enable_if_t<!is_pyobject<T>::value, int>>
object object_or_cast(T &&o) { return pybind11::cast(std::forward<T>(o)); }
struct overload_unused {}; // Placeholder type for the unneeded (and dead code) static variable in the OVERLOAD_INT macro
template <typename ret_type> using overload_caster_t = conditional_t<
cast_is_temporary_value_reference<ret_type>::value, make_caster<ret_type>, overload_unused>;
// Trampoline use: for reference/pointer types to value-converted values, we do a value cast, then
// store the result in the given variable. For other types, this is a no-op.
template <typename T> enable_if_t<cast_is_temporary_value_reference<T>::value, T> cast_ref(object &&o, make_caster<T> &caster) {
return cast_op<T>(load_type(caster, o));
}
template <typename T> enable_if_t<!cast_is_temporary_value_reference<T>::value, T> cast_ref(object &&, overload_unused &) {
pybind11_fail("Internal error: cast_ref fallback invoked"); }
// Trampoline use: Having a pybind11::cast with an invalid reference type is going to static_assert, even
// though if it's in dead code, so we provide a "trampoline" to pybind11::cast that only does anything in
// cases where pybind11::cast is valid.
template <typename T> enable_if_t<!cast_is_temporary_value_reference<T>::value, T> cast_safe(object &&o) {
return pybind11::cast<T>(std::move(o)); }
template <typename T> enable_if_t<cast_is_temporary_value_reference<T>::value, T> cast_safe(object &&) {
pybind11_fail("Internal error: cast_safe fallback invoked"); }
template <> inline void cast_safe<void>(object &&) {}
NAMESPACE_END(detail)
template <return_value_policy policy = return_value_policy::automatic_reference,
typename... Args> tuple make_tuple(Args&&... args_) {
const size_t size = sizeof...(Args);
std::array<object, size> args {
{ reinterpret_steal<object>(detail::make_caster<Args>::cast(
std::forward<Args>(args_), policy, nullptr))... }
};
for (auto &arg_value : args) {
if (!arg_value) {
#if defined(NDEBUG)
throw cast_error("make_tuple(): unable to convert arguments to Python object (compile in debug mode for details)");
#else
throw cast_error("make_tuple(): unable to convert arguments of types '" +
(std::string) type_id<std::tuple<Args...>>() + "' to Python object");
#endif
}
}
tuple result(size);
int counter = 0;
for (auto &arg_value : args)
PyTuple_SET_ITEM(result.ptr(), counter++, arg_value.release().ptr());
return result;
}
/// Annotation for keyword arguments
struct arg {
constexpr explicit arg(const char *name) : name(name) { }
template <typename T> arg_v operator=(T &&value) const;
const char *name;
};
/// Annotation for keyword arguments with values
struct arg_v : arg {
template <typename T>
arg_v(const char *name, T &&x, const char *descr = nullptr)
: arg(name),
value(reinterpret_steal<object>(
detail::make_caster<T>::cast(x, return_value_policy::automatic, {})
)),
descr(descr)
#if !defined(NDEBUG)
, type(type_id<T>())
#endif
{ }
object value;
const char *descr;
#if !defined(NDEBUG)
std::string type;
#endif
};
template <typename T>
arg_v arg::operator=(T &&value) const { return {name, std::forward<T>(value)}; }
/// Alias for backward compatibility -- to be removed in version 2.0
template <typename /*unused*/> using arg_t = arg_v;
inline namespace literals {
/// String literal version of arg
constexpr arg operator"" _a(const char *name, size_t) { return arg(name); }
}
NAMESPACE_BEGIN(detail)
/// Helper class which loads arguments for C++ functions called from Python
template <typename... Args>
class argument_loader {
using itypes = type_list<intrinsic_t<Args>...>;
using indices = make_index_sequence<sizeof...(Args)>;
public:
argument_loader() : value() {} // Helps gcc-7 properly initialize value
static constexpr auto has_kwargs = std::is_same<itypes, type_list<args, kwargs>>::value;
static constexpr auto has_args = has_kwargs || std::is_same<itypes, type_list<args>>::value;
static PYBIND11_DESCR arg_names() { return detail::concat(make_caster<Args>::name()...); }
bool load_args(handle args, handle kwargs) {
return load_impl(args, kwargs, itypes{});
}
template <typename Return, typename Func>
enable_if_t<!std::is_void<Return>::value, Return> call(Func &&f) {
return call_impl<Return>(std::forward<Func>(f), indices{});
}
template <typename Return, typename Func>
enable_if_t<std::is_void<Return>::value, void_type> call(Func &&f) {
call_impl<Return>(std::forward<Func>(f), indices{});
return void_type();
}
private:
bool load_impl(handle args_, handle, type_list<args>) {
std::get<0>(value).load(args_, true);
return true;
}
bool load_impl(handle args_, handle kwargs_, type_list<args, kwargs>) {
std::get<0>(value).load(args_, true);
std::get<1>(value).load(kwargs_, true);
return true;
}
bool load_impl(handle args, handle, ... /* anything else */) {
return load_impl_sequence(args, indices{});
}
static bool load_impl_sequence(handle, index_sequence<>) { return true; }
template <size_t... Is>
bool load_impl_sequence(handle src, index_sequence<Is...>) {
for (bool r : {std::get<Is>(value).load(PyTuple_GET_ITEM(src.ptr(), Is), true)...})
if (!r)
return false;
return true;
}
template <typename Return, typename Func, size_t... Is>
Return call_impl(Func &&f, index_sequence<Is...>) {
return std::forward<Func>(f)(cast_op<Args>(std::get<Is>(value))...);
}
std::tuple<make_caster<Args>...> value;
};
NAMESPACE_BEGIN(constexpr_impl)
/// Implementation details for constexpr functions
constexpr int first(int i) { return i; }
template <typename T, typename... Ts>
constexpr int first(int i, T v, Ts... vs) { return v ? i : first(i + 1, vs...); }
constexpr int last(int /*i*/, int result) { return result; }
template <typename T, typename... Ts>
constexpr int last(int i, int result, T v, Ts... vs) { return last(i + 1, v ? i : result, vs...); }
NAMESPACE_END(constexpr_impl)
/// Return the index of the first type in Ts which satisfies Predicate<T>
template <template<typename> class Predicate, typename... Ts>
constexpr int constexpr_first() { return constexpr_impl::first(0, Predicate<Ts>::value...); }
/// Return the index of the last type in Ts which satisfies Predicate<T>
template <template<typename> class Predicate, typename... Ts>
constexpr int constexpr_last() { return constexpr_impl::last(0, -1, Predicate<Ts>::value...); }
/// Helper class which collects only positional arguments for a Python function call.
/// A fancier version below can collect any argument, but this one is optimal for simple calls.
template <return_value_policy policy>
class simple_collector {
public:
template <typename... Ts>
explicit simple_collector(Ts &&...values)
: m_args(pybind11::make_tuple<policy>(std::forward<Ts>(values)...)) { }
const tuple &args() const & { return m_args; }
dict kwargs() const { return {}; }
tuple args() && { return std::move(m_args); }
/// Call a Python function and pass the collected arguments
object call(PyObject *ptr) const {
PyObject *result = PyObject_CallObject(ptr, m_args.ptr());
if (!result)
throw error_already_set();
return reinterpret_steal<object>(result);
}
private:
tuple m_args;
};
/// Helper class which collects positional, keyword, * and ** arguments for a Python function call
template <return_value_policy policy>
class unpacking_collector {
public:
template <typename... Ts>
explicit unpacking_collector(Ts &&...values) {
// Tuples aren't (easily) resizable so a list is needed for collection,
// but the actual function call strictly requires a tuple.
auto args_list = list();
int _[] = { 0, (process(args_list, std::forward<Ts>(values)), 0)... };
ignore_unused(_);
m_args = std::move(args_list);
}
const tuple &args() const & { return m_args; }
const dict &kwargs() const & { return m_kwargs; }
tuple args() && { return std::move(m_args); }
dict kwargs() && { return std::move(m_kwargs); }
/// Call a Python function and pass the collected arguments
object call(PyObject *ptr) const {
PyObject *result = PyObject_Call(ptr, m_args.ptr(), m_kwargs.ptr());
if (!result)
throw error_already_set();
return reinterpret_steal<object>(result);
}
private:
template <typename T>
void process(list &args_list, T &&x) {
auto o = reinterpret_steal<object>(detail::make_caster<T>::cast(std::forward<T>(x), policy, {}));
if (!o) {
#if defined(NDEBUG)
argument_cast_error();
#else
argument_cast_error(std::to_string(args_list.size()), type_id<T>());
#endif
}
args_list.append(o);
}
void process(list &args_list, detail::args_proxy ap) {
for (const auto &a : ap)
args_list.append(a);
}
void process(list &/*args_list*/, arg_v a) {
if (m_kwargs.contains(a.name)) {
#if defined(NDEBUG)
multiple_values_error();
#else
multiple_values_error(a.name);
#endif
}
if (!a.value) {
#if defined(NDEBUG)
argument_cast_error();
#else
argument_cast_error(a.name, a.type);
#endif
}
m_kwargs[a.name] = a.value;
}
void process(list &/*args_list*/, detail::kwargs_proxy kp) {
if (!kp)
return;
for (const auto &k : reinterpret_borrow<dict>(kp)) {
if (m_kwargs.contains(k.first)) {
#if defined(NDEBUG)
multiple_values_error();
#else
multiple_values_error(str(k.first));
#endif
}
m_kwargs[k.first] = k.second;
}
}
[[noreturn]] static void multiple_values_error() {
throw type_error("Got multiple values for keyword argument "
"(compile in debug mode for details)");
}
[[noreturn]] static void multiple_values_error(std::string name) {
throw type_error("Got multiple values for keyword argument '" + name + "'");
}
[[noreturn]] static void argument_cast_error() {
throw cast_error("Unable to convert call argument to Python object "
"(compile in debug mode for details)");
}
[[noreturn]] static void argument_cast_error(std::string name, std::string type) {
throw cast_error("Unable to convert call argument '" + name
+ "' of type '" + type + "' to Python object");
}
private:
tuple m_args;
dict m_kwargs;
};
/// Collect only positional arguments for a Python function call
template <return_value_policy policy, typename... Args,
typename = enable_if_t<all_of<is_positional<Args>...>::value>>
simple_collector<policy> collect_arguments(Args &&...args) {
return simple_collector<policy>(std::forward<Args>(args)...);
}
/// Collect all arguments, including keywords and unpacking (only instantiated when needed)
template <return_value_policy policy, typename... Args,
typename = enable_if_t<!all_of<is_positional<Args>...>::value>>
unpacking_collector<policy> collect_arguments(Args &&...args) {
// Following argument order rules for generalized unpacking according to PEP 448
static_assert(
constexpr_last<is_positional, Args...>() < constexpr_first<is_keyword_or_ds, Args...>()
&& constexpr_last<is_s_unpacking, Args...>() < constexpr_first<is_ds_unpacking, Args...>(),
"Invalid function call: positional args must precede keywords and ** unpacking; "
"* unpacking must precede ** unpacking"
);
return unpacking_collector<policy>(std::forward<Args>(args)...);
}
template <typename Derived>
template <return_value_policy policy, typename... Args>
object object_api<Derived>::operator()(Args &&...args) const {
return detail::collect_arguments<policy>(std::forward<Args>(args)...).call(derived().ptr());
}
template <typename Derived>
template <return_value_policy policy, typename... Args>
object object_api<Derived>::call(Args &&...args) const {
return operator()<policy>(std::forward<Args>(args)...);
}
NAMESPACE_END(detail)
#define PYBIND11_MAKE_OPAQUE(Type) \
namespace pybind11 { namespace detail { \
template<> class type_caster<Type> : public type_caster_base<Type> { }; \
}}
NAMESPACE_END(pybind11)
|