| #include "Python.h" | 
 | #include "structmember.h" | 
 |  | 
 | #ifdef STDC_HEADERS | 
 | #include <stddef.h> | 
 | #else | 
 | #include <sys/types.h>          /* For size_t */ | 
 | #endif | 
 |  | 
 | /*[clinic input] | 
 | module _collections | 
 | class _tuplegetter "_tuplegetterobject *" "&tuplegetter_type" | 
 | [clinic start generated code]*/ | 
 | /*[clinic end generated code: output=da39a3ee5e6b4b0d input=a8ece4ccad7e30ac]*/ | 
 |  | 
 | static PyTypeObject tuplegetter_type; | 
 | #include "clinic/_collectionsmodule.c.h" | 
 |  | 
 | /* collections module implementation of a deque() datatype | 
 |    Written and maintained by Raymond D. Hettinger <python@rcn.com> | 
 | */ | 
 |  | 
 | /* The block length may be set to any number over 1.  Larger numbers | 
 |  * reduce the number of calls to the memory allocator, give faster | 
 |  * indexing and rotation, and reduce the link to data overhead ratio. | 
 |  * Making the block length a power of two speeds-up the modulo | 
 |  * and division calculations in deque_item() and deque_ass_item(). | 
 |  */ | 
 |  | 
 | #define BLOCKLEN 64 | 
 | #define CENTER ((BLOCKLEN - 1) / 2) | 
 |  | 
 | /* Data for deque objects is stored in a doubly-linked list of fixed | 
 |  * length blocks.  This assures that appends or pops never move any | 
 |  * other data elements besides the one being appended or popped. | 
 |  * | 
 |  * Another advantage is that it completely avoids use of realloc(), | 
 |  * resulting in more predictable performance. | 
 |  * | 
 |  * Textbook implementations of doubly-linked lists store one datum | 
 |  * per link, but that gives them a 200% memory overhead (a prev and | 
 |  * next link for each datum) and it costs one malloc() call per data | 
 |  * element.  By using fixed-length blocks, the link to data ratio is | 
 |  * significantly improved and there are proportionally fewer calls | 
 |  * to malloc() and free().  The data blocks of consecutive pointers | 
 |  * also improve cache locality. | 
 |  * | 
 |  * The list of blocks is never empty, so d.leftblock and d.rightblock | 
 |  * are never equal to NULL.  The list is not circular. | 
 |  * | 
 |  * A deque d's first element is at d.leftblock[leftindex] | 
 |  * and its last element is at d.rightblock[rightindex]. | 
 |  * | 
 |  * Unlike Python slice indices, these indices are inclusive on both | 
 |  * ends.  This makes the algorithms for left and right operations | 
 |  * more symmetrical and it simplifies the design. | 
 |  * | 
 |  * The indices, d.leftindex and d.rightindex are always in the range: | 
 |  *     0 <= index < BLOCKLEN | 
 |  * | 
 |  * And their exact relationship is: | 
 |  *     (d.leftindex + d.len - 1) % BLOCKLEN == d.rightindex | 
 |  * | 
 |  * Whenever d.leftblock == d.rightblock, then: | 
 |  *     d.leftindex + d.len - 1 == d.rightindex | 
 |  * | 
 |  * However, when d.leftblock != d.rightblock, the d.leftindex and | 
 |  * d.rightindex become indices into distinct blocks and either may | 
 |  * be larger than the other. | 
 |  * | 
 |  * Empty deques have: | 
 |  *     d.len == 0 | 
 |  *     d.leftblock == d.rightblock | 
 |  *     d.leftindex == CENTER + 1 | 
 |  *     d.rightindex == CENTER | 
 |  * | 
 |  * Checking for d.len == 0 is the intended way to see whether d is empty. | 
 |  */ | 
 |  | 
 | typedef struct BLOCK { | 
 |     struct BLOCK *leftlink; | 
 |     PyObject *data[BLOCKLEN]; | 
 |     struct BLOCK *rightlink; | 
 | } block; | 
 |  | 
 | typedef struct { | 
 |     PyObject_VAR_HEAD | 
 |     block *leftblock; | 
 |     block *rightblock; | 
 |     Py_ssize_t leftindex;       /* 0 <= leftindex < BLOCKLEN */ | 
 |     Py_ssize_t rightindex;      /* 0 <= rightindex < BLOCKLEN */ | 
 |     size_t state;               /* incremented whenever the indices move */ | 
 |     Py_ssize_t maxlen;          /* maxlen is -1 for unbounded deques */ | 
 |     PyObject *weakreflist; | 
 | } dequeobject; | 
 |  | 
 | static PyTypeObject deque_type; | 
 |  | 
 | /* For debug builds, add error checking to track the endpoints | 
 |  * in the chain of links.  The goal is to make sure that link | 
 |  * assignments only take place at endpoints so that links already | 
 |  * in use do not get overwritten. | 
 |  * | 
 |  * CHECK_END should happen before each assignment to a block's link field. | 
 |  * MARK_END should happen whenever a link field becomes a new endpoint. | 
 |  * This happens when new blocks are added or whenever an existing | 
 |  * block is freed leaving another existing block as the new endpoint. | 
 |  */ | 
 |  | 
 | #ifndef NDEBUG | 
 | #define MARK_END(link)  link = NULL; | 
 | #define CHECK_END(link) assert(link == NULL); | 
 | #define CHECK_NOT_END(link) assert(link != NULL); | 
 | #else | 
 | #define MARK_END(link) | 
 | #define CHECK_END(link) | 
 | #define CHECK_NOT_END(link) | 
 | #endif | 
 |  | 
 | /* A simple freelisting scheme is used to minimize calls to the memory | 
 |    allocator.  It accommodates common use cases where new blocks are being | 
 |    added at about the same rate as old blocks are being freed. | 
 |  */ | 
 |  | 
 | #define MAXFREEBLOCKS 16 | 
 | static Py_ssize_t numfreeblocks = 0; | 
 | static block *freeblocks[MAXFREEBLOCKS]; | 
 |  | 
 | static block * | 
 | newblock(void) { | 
 |     block *b; | 
 |     if (numfreeblocks) { | 
 |         numfreeblocks--; | 
 |         return freeblocks[numfreeblocks]; | 
 |     } | 
 |     b = PyMem_Malloc(sizeof(block)); | 
 |     if (b != NULL) { | 
 |         return b; | 
 |     } | 
 |     PyErr_NoMemory(); | 
 |     return NULL; | 
 | } | 
 |  | 
 | static void | 
 | freeblock(block *b) | 
 | { | 
 |     if (numfreeblocks < MAXFREEBLOCKS) { | 
 |         freeblocks[numfreeblocks] = b; | 
 |         numfreeblocks++; | 
 |     } else { | 
 |         PyMem_Free(b); | 
 |     } | 
 | } | 
 |  | 
 | static PyObject * | 
 | deque_new(PyTypeObject *type, PyObject *args, PyObject *kwds) | 
 | { | 
 |     dequeobject *deque; | 
 |     block *b; | 
 |  | 
 |     /* create dequeobject structure */ | 
 |     deque = (dequeobject *)type->tp_alloc(type, 0); | 
 |     if (deque == NULL) | 
 |         return NULL; | 
 |  | 
 |     b = newblock(); | 
 |     if (b == NULL) { | 
 |         Py_DECREF(deque); | 
 |         return NULL; | 
 |     } | 
 |     MARK_END(b->leftlink); | 
 |     MARK_END(b->rightlink); | 
 |  | 
 |     assert(BLOCKLEN >= 2); | 
 |     Py_SIZE(deque) = 0; | 
 |     deque->leftblock = b; | 
 |     deque->rightblock = b; | 
 |     deque->leftindex = CENTER + 1; | 
 |     deque->rightindex = CENTER; | 
 |     deque->state = 0; | 
 |     deque->maxlen = -1; | 
 |     deque->weakreflist = NULL; | 
 |  | 
 |     return (PyObject *)deque; | 
 | } | 
 |  | 
 | static PyObject * | 
 | deque_pop(dequeobject *deque, PyObject *unused) | 
 | { | 
 |     PyObject *item; | 
 |     block *prevblock; | 
 |  | 
 |     if (Py_SIZE(deque) == 0) { | 
 |         PyErr_SetString(PyExc_IndexError, "pop from an empty deque"); | 
 |         return NULL; | 
 |     } | 
 |     item = deque->rightblock->data[deque->rightindex]; | 
 |     deque->rightindex--; | 
 |     Py_SIZE(deque)--; | 
 |     deque->state++; | 
 |  | 
 |     if (deque->rightindex < 0) { | 
 |         if (Py_SIZE(deque)) { | 
 |             prevblock = deque->rightblock->leftlink; | 
 |             assert(deque->leftblock != deque->rightblock); | 
 |             freeblock(deque->rightblock); | 
 |             CHECK_NOT_END(prevblock); | 
 |             MARK_END(prevblock->rightlink); | 
 |             deque->rightblock = prevblock; | 
 |             deque->rightindex = BLOCKLEN - 1; | 
 |         } else { | 
 |             assert(deque->leftblock == deque->rightblock); | 
 |             assert(deque->leftindex == deque->rightindex+1); | 
 |             /* re-center instead of freeing a block */ | 
 |             deque->leftindex = CENTER + 1; | 
 |             deque->rightindex = CENTER; | 
 |         } | 
 |     } | 
 |     return item; | 
 | } | 
 |  | 
 | PyDoc_STRVAR(pop_doc, "Remove and return the rightmost element."); | 
 |  | 
 | static PyObject * | 
 | deque_popleft(dequeobject *deque, PyObject *unused) | 
 | { | 
 |     PyObject *item; | 
 |     block *prevblock; | 
 |  | 
 |     if (Py_SIZE(deque) == 0) { | 
 |         PyErr_SetString(PyExc_IndexError, "pop from an empty deque"); | 
 |         return NULL; | 
 |     } | 
 |     assert(deque->leftblock != NULL); | 
 |     item = deque->leftblock->data[deque->leftindex]; | 
 |     deque->leftindex++; | 
 |     Py_SIZE(deque)--; | 
 |     deque->state++; | 
 |  | 
 |     if (deque->leftindex == BLOCKLEN) { | 
 |         if (Py_SIZE(deque)) { | 
 |             assert(deque->leftblock != deque->rightblock); | 
 |             prevblock = deque->leftblock->rightlink; | 
 |             freeblock(deque->leftblock); | 
 |             CHECK_NOT_END(prevblock); | 
 |             MARK_END(prevblock->leftlink); | 
 |             deque->leftblock = prevblock; | 
 |             deque->leftindex = 0; | 
 |         } else { | 
 |             assert(deque->leftblock == deque->rightblock); | 
 |             assert(deque->leftindex == deque->rightindex+1); | 
 |             /* re-center instead of freeing a block */ | 
 |             deque->leftindex = CENTER + 1; | 
 |             deque->rightindex = CENTER; | 
 |         } | 
 |     } | 
 |     return item; | 
 | } | 
 |  | 
 | PyDoc_STRVAR(popleft_doc, "Remove and return the leftmost element."); | 
 |  | 
 | /* The deque's size limit is d.maxlen.  The limit can be zero or positive. | 
 |  * If there is no limit, then d.maxlen == -1. | 
 |  * | 
 |  * After an item is added to a deque, we check to see if the size has | 
 |  * grown past the limit. If it has, we get the size back down to the limit | 
 |  * by popping an item off of the opposite end.  The methods that can | 
 |  * trigger this are append(), appendleft(), extend(), and extendleft(). | 
 |  * | 
 |  * The macro to check whether a deque needs to be trimmed uses a single | 
 |  * unsigned test that returns true whenever 0 <= maxlen < Py_SIZE(deque). | 
 |  */ | 
 |  | 
 | #define NEEDS_TRIM(deque, maxlen) ((size_t)(maxlen) < (size_t)(Py_SIZE(deque))) | 
 |  | 
 | static inline int | 
 | deque_append_internal(dequeobject *deque, PyObject *item, Py_ssize_t maxlen) | 
 | { | 
 |     if (deque->rightindex == BLOCKLEN - 1) { | 
 |         block *b = newblock(); | 
 |         if (b == NULL) | 
 |             return -1; | 
 |         b->leftlink = deque->rightblock; | 
 |         CHECK_END(deque->rightblock->rightlink); | 
 |         deque->rightblock->rightlink = b; | 
 |         deque->rightblock = b; | 
 |         MARK_END(b->rightlink); | 
 |         deque->rightindex = -1; | 
 |     } | 
 |     Py_SIZE(deque)++; | 
 |     deque->rightindex++; | 
 |     deque->rightblock->data[deque->rightindex] = item; | 
 |     if (NEEDS_TRIM(deque, maxlen)) { | 
 |         PyObject *olditem = deque_popleft(deque, NULL); | 
 |         Py_DECREF(olditem); | 
 |     } else { | 
 |         deque->state++; | 
 |     } | 
 |     return 0; | 
 | } | 
 |  | 
 | static PyObject * | 
 | deque_append(dequeobject *deque, PyObject *item) | 
 | { | 
 |     Py_INCREF(item); | 
 |     if (deque_append_internal(deque, item, deque->maxlen) < 0) | 
 |         return NULL; | 
 |     Py_RETURN_NONE; | 
 | } | 
 |  | 
 | PyDoc_STRVAR(append_doc, "Add an element to the right side of the deque."); | 
 |  | 
 | static inline int | 
 | deque_appendleft_internal(dequeobject *deque, PyObject *item, Py_ssize_t maxlen) | 
 | { | 
 |     if (deque->leftindex == 0) { | 
 |         block *b = newblock(); | 
 |         if (b == NULL) | 
 |             return -1; | 
 |         b->rightlink = deque->leftblock; | 
 |         CHECK_END(deque->leftblock->leftlink); | 
 |         deque->leftblock->leftlink = b; | 
 |         deque->leftblock = b; | 
 |         MARK_END(b->leftlink); | 
 |         deque->leftindex = BLOCKLEN; | 
 |     } | 
 |     Py_SIZE(deque)++; | 
 |     deque->leftindex--; | 
 |     deque->leftblock->data[deque->leftindex] = item; | 
 |     if (NEEDS_TRIM(deque, deque->maxlen)) { | 
 |         PyObject *olditem = deque_pop(deque, NULL); | 
 |         Py_DECREF(olditem); | 
 |     } else { | 
 |         deque->state++; | 
 |     } | 
 |     return 0; | 
 | } | 
 |  | 
 | static PyObject * | 
 | deque_appendleft(dequeobject *deque, PyObject *item) | 
 | { | 
 |     Py_INCREF(item); | 
 |     if (deque_appendleft_internal(deque, item, deque->maxlen) < 0) | 
 |         return NULL; | 
 |     Py_RETURN_NONE; | 
 | } | 
 |  | 
 | PyDoc_STRVAR(appendleft_doc, "Add an element to the left side of the deque."); | 
 |  | 
 | static PyObject* | 
 | finalize_iterator(PyObject *it) | 
 | { | 
 |     if (PyErr_Occurred()) { | 
 |         if (PyErr_ExceptionMatches(PyExc_StopIteration)) | 
 |             PyErr_Clear(); | 
 |         else { | 
 |             Py_DECREF(it); | 
 |             return NULL; | 
 |         } | 
 |     } | 
 |     Py_DECREF(it); | 
 |     Py_RETURN_NONE; | 
 | } | 
 |  | 
 | /* Run an iterator to exhaustion.  Shortcut for | 
 |    the extend/extendleft methods when maxlen == 0. */ | 
 | static PyObject* | 
 | consume_iterator(PyObject *it) | 
 | { | 
 |     PyObject *(*iternext)(PyObject *); | 
 |     PyObject *item; | 
 |  | 
 |     iternext = *Py_TYPE(it)->tp_iternext; | 
 |     while ((item = iternext(it)) != NULL) { | 
 |         Py_DECREF(item); | 
 |     } | 
 |     return finalize_iterator(it); | 
 | } | 
 |  | 
 | static PyObject * | 
 | deque_extend(dequeobject *deque, PyObject *iterable) | 
 | { | 
 |     PyObject *it, *item; | 
 |     PyObject *(*iternext)(PyObject *); | 
 |     Py_ssize_t maxlen = deque->maxlen; | 
 |  | 
 |     /* Handle case where id(deque) == id(iterable) */ | 
 |     if ((PyObject *)deque == iterable) { | 
 |         PyObject *result; | 
 |         PyObject *s = PySequence_List(iterable); | 
 |         if (s == NULL) | 
 |             return NULL; | 
 |         result = deque_extend(deque, s); | 
 |         Py_DECREF(s); | 
 |         return result; | 
 |     } | 
 |  | 
 |     it = PyObject_GetIter(iterable); | 
 |     if (it == NULL) | 
 |         return NULL; | 
 |  | 
 |     if (maxlen == 0) | 
 |         return consume_iterator(it); | 
 |  | 
 |     /* Space saving heuristic.  Start filling from the left */ | 
 |     if (Py_SIZE(deque) == 0) { | 
 |         assert(deque->leftblock == deque->rightblock); | 
 |         assert(deque->leftindex == deque->rightindex+1); | 
 |         deque->leftindex = 1; | 
 |         deque->rightindex = 0; | 
 |     } | 
 |  | 
 |     iternext = *Py_TYPE(it)->tp_iternext; | 
 |     while ((item = iternext(it)) != NULL) { | 
 |         if (deque_append_internal(deque, item, maxlen) == -1) { | 
 |             Py_DECREF(item); | 
 |             Py_DECREF(it); | 
 |             return NULL; | 
 |         } | 
 |     } | 
 |     return finalize_iterator(it); | 
 | } | 
 |  | 
 | PyDoc_STRVAR(extend_doc, | 
 | "Extend the right side of the deque with elements from the iterable"); | 
 |  | 
 | static PyObject * | 
 | deque_extendleft(dequeobject *deque, PyObject *iterable) | 
 | { | 
 |     PyObject *it, *item; | 
 |     PyObject *(*iternext)(PyObject *); | 
 |     Py_ssize_t maxlen = deque->maxlen; | 
 |  | 
 |     /* Handle case where id(deque) == id(iterable) */ | 
 |     if ((PyObject *)deque == iterable) { | 
 |         PyObject *result; | 
 |         PyObject *s = PySequence_List(iterable); | 
 |         if (s == NULL) | 
 |             return NULL; | 
 |         result = deque_extendleft(deque, s); | 
 |         Py_DECREF(s); | 
 |         return result; | 
 |     } | 
 |  | 
 |     it = PyObject_GetIter(iterable); | 
 |     if (it == NULL) | 
 |         return NULL; | 
 |  | 
 |     if (maxlen == 0) | 
 |         return consume_iterator(it); | 
 |  | 
 |     /* Space saving heuristic.  Start filling from the right */ | 
 |     if (Py_SIZE(deque) == 0) { | 
 |         assert(deque->leftblock == deque->rightblock); | 
 |         assert(deque->leftindex == deque->rightindex+1); | 
 |         deque->leftindex = BLOCKLEN - 1; | 
 |         deque->rightindex = BLOCKLEN - 2; | 
 |     } | 
 |  | 
 |     iternext = *Py_TYPE(it)->tp_iternext; | 
 |     while ((item = iternext(it)) != NULL) { | 
 |         if (deque_appendleft_internal(deque, item, maxlen) == -1) { | 
 |             Py_DECREF(item); | 
 |             Py_DECREF(it); | 
 |             return NULL; | 
 |         } | 
 |     } | 
 |     return finalize_iterator(it); | 
 | } | 
 |  | 
 | PyDoc_STRVAR(extendleft_doc, | 
 | "Extend the left side of the deque with elements from the iterable"); | 
 |  | 
 | static PyObject * | 
 | deque_inplace_concat(dequeobject *deque, PyObject *other) | 
 | { | 
 |     PyObject *result; | 
 |  | 
 |     result = deque_extend(deque, other); | 
 |     if (result == NULL) | 
 |         return result; | 
 |     Py_INCREF(deque); | 
 |     Py_DECREF(result); | 
 |     return (PyObject *)deque; | 
 | } | 
 |  | 
 | static PyObject * | 
 | deque_copy(PyObject *deque, PyObject *Py_UNUSED(ignored)) | 
 | { | 
 |     PyObject *result; | 
 |     dequeobject *old_deque = (dequeobject *)deque; | 
 |     if (Py_TYPE(deque) == &deque_type) { | 
 |         dequeobject *new_deque; | 
 |         PyObject *rv; | 
 |  | 
 |         new_deque = (dequeobject *)deque_new(&deque_type, (PyObject *)NULL, (PyObject *)NULL); | 
 |         if (new_deque == NULL) | 
 |             return NULL; | 
 |         new_deque->maxlen = old_deque->maxlen; | 
 |         /* Fast path for the deque_repeat() common case where len(deque) == 1 */ | 
 |         if (Py_SIZE(deque) == 1) { | 
 |             PyObject *item = old_deque->leftblock->data[old_deque->leftindex]; | 
 |             rv = deque_append(new_deque, item); | 
 |         } else { | 
 |             rv = deque_extend(new_deque, deque); | 
 |         } | 
 |         if (rv != NULL) { | 
 |             Py_DECREF(rv); | 
 |             return (PyObject *)new_deque; | 
 |         } | 
 |         Py_DECREF(new_deque); | 
 |         return NULL; | 
 |     } | 
 |     if (old_deque->maxlen < 0) | 
 |         result = _PyObject_CallOneArg((PyObject *)(Py_TYPE(deque)), deque); | 
 |     else | 
 |         result = PyObject_CallFunction((PyObject *)(Py_TYPE(deque)), "Oi", | 
 |                                        deque, old_deque->maxlen, NULL); | 
 |     if (result != NULL && !PyObject_TypeCheck(result, &deque_type)) { | 
 |         PyErr_Format(PyExc_TypeError, | 
 |                      "%.200s() must return a deque, not %.200s", | 
 |                      Py_TYPE(deque)->tp_name, Py_TYPE(result)->tp_name); | 
 |         Py_DECREF(result); | 
 |         return NULL; | 
 |     } | 
 |     return result; | 
 | } | 
 |  | 
 | PyDoc_STRVAR(copy_doc, "Return a shallow copy of a deque."); | 
 |  | 
 | static PyObject * | 
 | deque_concat(dequeobject *deque, PyObject *other) | 
 | { | 
 |     PyObject *new_deque, *result; | 
 |     int rv; | 
 |  | 
 |     rv = PyObject_IsInstance(other, (PyObject *)&deque_type); | 
 |     if (rv <= 0) { | 
 |         if (rv == 0) { | 
 |             PyErr_Format(PyExc_TypeError, | 
 |                          "can only concatenate deque (not \"%.200s\") to deque", | 
 |                          other->ob_type->tp_name); | 
 |         } | 
 |         return NULL; | 
 |     } | 
 |  | 
 |     new_deque = deque_copy((PyObject *)deque, NULL); | 
 |     if (new_deque == NULL) | 
 |         return NULL; | 
 |     result = deque_extend((dequeobject *)new_deque, other); | 
 |     if (result == NULL) { | 
 |         Py_DECREF(new_deque); | 
 |         return NULL; | 
 |     } | 
 |     Py_DECREF(result); | 
 |     return new_deque; | 
 | } | 
 |  | 
 | static int | 
 | deque_clear(dequeobject *deque) | 
 | { | 
 |     block *b; | 
 |     block *prevblock; | 
 |     block *leftblock; | 
 |     Py_ssize_t leftindex; | 
 |     Py_ssize_t n, m; | 
 |     PyObject *item; | 
 |     PyObject **itemptr, **limit; | 
 |  | 
 |     if (Py_SIZE(deque) == 0) | 
 |         return 0; | 
 |  | 
 |     /* During the process of clearing a deque, decrefs can cause the | 
 |        deque to mutate.  To avoid fatal confusion, we have to make the | 
 |        deque empty before clearing the blocks and never refer to | 
 |        anything via deque->ref while clearing.  (This is the same | 
 |        technique used for clearing lists, sets, and dicts.) | 
 |  | 
 |        Making the deque empty requires allocating a new empty block.  In | 
 |        the unlikely event that memory is full, we fall back to an | 
 |        alternate method that doesn't require a new block.  Repeating | 
 |        pops in a while-loop is slower, possibly re-entrant (and a clever | 
 |        adversary could cause it to never terminate). | 
 |     */ | 
 |  | 
 |     b = newblock(); | 
 |     if (b == NULL) { | 
 |         PyErr_Clear(); | 
 |         goto alternate_method; | 
 |     } | 
 |  | 
 |     /* Remember the old size, leftblock, and leftindex */ | 
 |     n = Py_SIZE(deque); | 
 |     leftblock = deque->leftblock; | 
 |     leftindex = deque->leftindex; | 
 |  | 
 |     /* Set the deque to be empty using the newly allocated block */ | 
 |     MARK_END(b->leftlink); | 
 |     MARK_END(b->rightlink); | 
 |     Py_SIZE(deque) = 0; | 
 |     deque->leftblock = b; | 
 |     deque->rightblock = b; | 
 |     deque->leftindex = CENTER + 1; | 
 |     deque->rightindex = CENTER; | 
 |     deque->state++; | 
 |  | 
 |     /* Now the old size, leftblock, and leftindex are disconnected from | 
 |        the empty deque and we can use them to decref the pointers. | 
 |     */ | 
 |     m = (BLOCKLEN - leftindex > n) ? n : BLOCKLEN - leftindex; | 
 |     itemptr = &leftblock->data[leftindex]; | 
 |     limit = itemptr + m; | 
 |     n -= m; | 
 |     while (1) { | 
 |         if (itemptr == limit) { | 
 |             if (n == 0) | 
 |                 break; | 
 |             CHECK_NOT_END(leftblock->rightlink); | 
 |             prevblock = leftblock; | 
 |             leftblock = leftblock->rightlink; | 
 |             m = (n > BLOCKLEN) ? BLOCKLEN : n; | 
 |             itemptr = leftblock->data; | 
 |             limit = itemptr + m; | 
 |             n -= m; | 
 |             freeblock(prevblock); | 
 |         } | 
 |         item = *(itemptr++); | 
 |         Py_DECREF(item); | 
 |     } | 
 |     CHECK_END(leftblock->rightlink); | 
 |     freeblock(leftblock); | 
 |     return 0; | 
 |  | 
 |   alternate_method: | 
 |     while (Py_SIZE(deque)) { | 
 |         item = deque_pop(deque, NULL); | 
 |         assert (item != NULL); | 
 |         Py_DECREF(item); | 
 |     } | 
 |     return 0; | 
 | } | 
 |  | 
 | static PyObject * | 
 | deque_clearmethod(dequeobject *deque, PyObject *Py_UNUSED(ignored)) | 
 | { | 
 |     deque_clear(deque); | 
 |     Py_RETURN_NONE; | 
 | } | 
 |  | 
 | PyDoc_STRVAR(clear_doc, "Remove all elements from the deque."); | 
 |  | 
 | static PyObject * | 
 | deque_inplace_repeat(dequeobject *deque, Py_ssize_t n) | 
 | { | 
 |     Py_ssize_t i, m, size; | 
 |     PyObject *seq; | 
 |     PyObject *rv; | 
 |  | 
 |     size = Py_SIZE(deque); | 
 |     if (size == 0 || n == 1) { | 
 |         Py_INCREF(deque); | 
 |         return (PyObject *)deque; | 
 |     } | 
 |  | 
 |     if (n <= 0) { | 
 |         deque_clear(deque); | 
 |         Py_INCREF(deque); | 
 |         return (PyObject *)deque; | 
 |     } | 
 |  | 
 |     if (size == 1) { | 
 |         /* common case, repeating a single element */ | 
 |         PyObject *item = deque->leftblock->data[deque->leftindex]; | 
 |  | 
 |         if (deque->maxlen >= 0 && n > deque->maxlen) | 
 |             n = deque->maxlen; | 
 |  | 
 |         deque->state++; | 
 |         for (i = 0 ; i < n-1 ; ) { | 
 |             if (deque->rightindex == BLOCKLEN - 1) { | 
 |                 block *b = newblock(); | 
 |                 if (b == NULL) { | 
 |                     Py_SIZE(deque) += i; | 
 |                     return NULL; | 
 |                 } | 
 |                 b->leftlink = deque->rightblock; | 
 |                 CHECK_END(deque->rightblock->rightlink); | 
 |                 deque->rightblock->rightlink = b; | 
 |                 deque->rightblock = b; | 
 |                 MARK_END(b->rightlink); | 
 |                 deque->rightindex = -1; | 
 |             } | 
 |             m = n - 1 - i; | 
 |             if (m > BLOCKLEN - 1 - deque->rightindex) | 
 |                 m = BLOCKLEN - 1 - deque->rightindex; | 
 |             i += m; | 
 |             while (m--) { | 
 |                 deque->rightindex++; | 
 |                 Py_INCREF(item); | 
 |                 deque->rightblock->data[deque->rightindex] = item; | 
 |             } | 
 |         } | 
 |         Py_SIZE(deque) += i; | 
 |         Py_INCREF(deque); | 
 |         return (PyObject *)deque; | 
 |     } | 
 |  | 
 |     if ((size_t)size > PY_SSIZE_T_MAX / (size_t)n) { | 
 |         return PyErr_NoMemory(); | 
 |     } | 
 |  | 
 |     seq = PySequence_List((PyObject *)deque); | 
 |     if (seq == NULL) | 
 |         return seq; | 
 |  | 
 |     /* Reduce the number of repetitions when maxlen would be exceeded */ | 
 |     if (deque->maxlen >= 0 && n * size > deque->maxlen) | 
 |         n = (deque->maxlen + size - 1) / size; | 
 |  | 
 |     for (i = 0 ; i < n-1 ; i++) { | 
 |         rv = deque_extend(deque, seq); | 
 |         if (rv == NULL) { | 
 |             Py_DECREF(seq); | 
 |             return NULL; | 
 |         } | 
 |         Py_DECREF(rv); | 
 |     } | 
 |     Py_INCREF(deque); | 
 |     Py_DECREF(seq); | 
 |     return (PyObject *)deque; | 
 | } | 
 |  | 
 | static PyObject * | 
 | deque_repeat(dequeobject *deque, Py_ssize_t n) | 
 | { | 
 |     dequeobject *new_deque; | 
 |     PyObject *rv; | 
 |  | 
 |     new_deque = (dequeobject *)deque_copy((PyObject *) deque, NULL); | 
 |     if (new_deque == NULL) | 
 |         return NULL; | 
 |     rv = deque_inplace_repeat(new_deque, n); | 
 |     Py_DECREF(new_deque); | 
 |     return rv; | 
 | } | 
 |  | 
 | /* The rotate() method is part of the public API and is used internally | 
 | as a primitive for other methods. | 
 |  | 
 | Rotation by 1 or -1 is a common case, so any optimizations for high | 
 | volume rotations should take care not to penalize the common case. | 
 |  | 
 | Conceptually, a rotate by one is equivalent to a pop on one side and an | 
 | append on the other.  However, a pop/append pair is unnecessarily slow | 
 | because it requires an incref/decref pair for an object located randomly | 
 | in memory.  It is better to just move the object pointer from one block | 
 | to the next without changing the reference count. | 
 |  | 
 | When moving batches of pointers, it is tempting to use memcpy() but that | 
 | proved to be slower than a simple loop for a variety of reasons. | 
 | Memcpy() cannot know in advance that we're copying pointers instead of | 
 | bytes, that the source and destination are pointer aligned and | 
 | non-overlapping, that moving just one pointer is a common case, that we | 
 | never need to move more than BLOCKLEN pointers, and that at least one | 
 | pointer is always moved. | 
 |  | 
 | For high volume rotations, newblock() and freeblock() are never called | 
 | more than once.  Previously emptied blocks are immediately reused as a | 
 | destination block.  If a block is left-over at the end, it is freed. | 
 | */ | 
 |  | 
 | static int | 
 | _deque_rotate(dequeobject *deque, Py_ssize_t n) | 
 | { | 
 |     block *b = NULL; | 
 |     block *leftblock = deque->leftblock; | 
 |     block *rightblock = deque->rightblock; | 
 |     Py_ssize_t leftindex = deque->leftindex; | 
 |     Py_ssize_t rightindex = deque->rightindex; | 
 |     Py_ssize_t len=Py_SIZE(deque), halflen=len>>1; | 
 |     int rv = -1; | 
 |  | 
 |     if (len <= 1) | 
 |         return 0; | 
 |     if (n > halflen || n < -halflen) { | 
 |         n %= len; | 
 |         if (n > halflen) | 
 |             n -= len; | 
 |         else if (n < -halflen) | 
 |             n += len; | 
 |     } | 
 |     assert(len > 1); | 
 |     assert(-halflen <= n && n <= halflen); | 
 |  | 
 |     deque->state++; | 
 |     while (n > 0) { | 
 |         if (leftindex == 0) { | 
 |             if (b == NULL) { | 
 |                 b = newblock(); | 
 |                 if (b == NULL) | 
 |                     goto done; | 
 |             } | 
 |             b->rightlink = leftblock; | 
 |             CHECK_END(leftblock->leftlink); | 
 |             leftblock->leftlink = b; | 
 |             leftblock = b; | 
 |             MARK_END(b->leftlink); | 
 |             leftindex = BLOCKLEN; | 
 |             b = NULL; | 
 |         } | 
 |         assert(leftindex > 0); | 
 |         { | 
 |             PyObject **src, **dest; | 
 |             Py_ssize_t m = n; | 
 |  | 
 |             if (m > rightindex + 1) | 
 |                 m = rightindex + 1; | 
 |             if (m > leftindex) | 
 |                 m = leftindex; | 
 |             assert (m > 0 && m <= len); | 
 |             rightindex -= m; | 
 |             leftindex -= m; | 
 |             src = &rightblock->data[rightindex + 1]; | 
 |             dest = &leftblock->data[leftindex]; | 
 |             n -= m; | 
 |             do { | 
 |                 *(dest++) = *(src++); | 
 |             } while (--m); | 
 |         } | 
 |         if (rightindex < 0) { | 
 |             assert(leftblock != rightblock); | 
 |             assert(b == NULL); | 
 |             b = rightblock; | 
 |             CHECK_NOT_END(rightblock->leftlink); | 
 |             rightblock = rightblock->leftlink; | 
 |             MARK_END(rightblock->rightlink); | 
 |             rightindex = BLOCKLEN - 1; | 
 |         } | 
 |     } | 
 |     while (n < 0) { | 
 |         if (rightindex == BLOCKLEN - 1) { | 
 |             if (b == NULL) { | 
 |                 b = newblock(); | 
 |                 if (b == NULL) | 
 |                     goto done; | 
 |             } | 
 |             b->leftlink = rightblock; | 
 |             CHECK_END(rightblock->rightlink); | 
 |             rightblock->rightlink = b; | 
 |             rightblock = b; | 
 |             MARK_END(b->rightlink); | 
 |             rightindex = -1; | 
 |             b = NULL; | 
 |         } | 
 |         assert (rightindex < BLOCKLEN - 1); | 
 |         { | 
 |             PyObject **src, **dest; | 
 |             Py_ssize_t m = -n; | 
 |  | 
 |             if (m > BLOCKLEN - leftindex) | 
 |                 m = BLOCKLEN - leftindex; | 
 |             if (m > BLOCKLEN - 1 - rightindex) | 
 |                 m = BLOCKLEN - 1 - rightindex; | 
 |             assert (m > 0 && m <= len); | 
 |             src = &leftblock->data[leftindex]; | 
 |             dest = &rightblock->data[rightindex + 1]; | 
 |             leftindex += m; | 
 |             rightindex += m; | 
 |             n += m; | 
 |             do { | 
 |                 *(dest++) = *(src++); | 
 |             } while (--m); | 
 |         } | 
 |         if (leftindex == BLOCKLEN) { | 
 |             assert(leftblock != rightblock); | 
 |             assert(b == NULL); | 
 |             b = leftblock; | 
 |             CHECK_NOT_END(leftblock->rightlink); | 
 |             leftblock = leftblock->rightlink; | 
 |             MARK_END(leftblock->leftlink); | 
 |             leftindex = 0; | 
 |         } | 
 |     } | 
 |     rv = 0; | 
 | done: | 
 |     if (b != NULL) | 
 |         freeblock(b); | 
 |     deque->leftblock = leftblock; | 
 |     deque->rightblock = rightblock; | 
 |     deque->leftindex = leftindex; | 
 |     deque->rightindex = rightindex; | 
 |  | 
 |     return rv; | 
 | } | 
 |  | 
 | static PyObject * | 
 | deque_rotate(dequeobject *deque, PyObject *const *args, Py_ssize_t nargs) | 
 | { | 
 |     Py_ssize_t n=1; | 
 |  | 
 |     if (!_PyArg_ParseStack(args, nargs, "|n:rotate", &n)) { | 
 |         return NULL; | 
 |     } | 
 |  | 
 |     if (!_deque_rotate(deque, n)) | 
 |         Py_RETURN_NONE; | 
 |     return NULL; | 
 | } | 
 |  | 
 | PyDoc_STRVAR(rotate_doc, | 
 | "Rotate the deque n steps to the right (default n=1).  If n is negative, rotates left."); | 
 |  | 
 | static PyObject * | 
 | deque_reverse(dequeobject *deque, PyObject *unused) | 
 | { | 
 |     block *leftblock = deque->leftblock; | 
 |     block *rightblock = deque->rightblock; | 
 |     Py_ssize_t leftindex = deque->leftindex; | 
 |     Py_ssize_t rightindex = deque->rightindex; | 
 |     Py_ssize_t n = Py_SIZE(deque) >> 1; | 
 |     PyObject *tmp; | 
 |  | 
 |     while (--n >= 0) { | 
 |         /* Validate that pointers haven't met in the middle */ | 
 |         assert(leftblock != rightblock || leftindex < rightindex); | 
 |         CHECK_NOT_END(leftblock); | 
 |         CHECK_NOT_END(rightblock); | 
 |  | 
 |         /* Swap */ | 
 |         tmp = leftblock->data[leftindex]; | 
 |         leftblock->data[leftindex] = rightblock->data[rightindex]; | 
 |         rightblock->data[rightindex] = tmp; | 
 |  | 
 |         /* Advance left block/index pair */ | 
 |         leftindex++; | 
 |         if (leftindex == BLOCKLEN) { | 
 |             leftblock = leftblock->rightlink; | 
 |             leftindex = 0; | 
 |         } | 
 |  | 
 |         /* Step backwards with the right block/index pair */ | 
 |         rightindex--; | 
 |         if (rightindex < 0) { | 
 |             rightblock = rightblock->leftlink; | 
 |             rightindex = BLOCKLEN - 1; | 
 |         } | 
 |     } | 
 |     Py_RETURN_NONE; | 
 | } | 
 |  | 
 | PyDoc_STRVAR(reverse_doc, | 
 | "D.reverse() -- reverse *IN PLACE*"); | 
 |  | 
 | static PyObject * | 
 | deque_count(dequeobject *deque, PyObject *v) | 
 | { | 
 |     block *b = deque->leftblock; | 
 |     Py_ssize_t index = deque->leftindex; | 
 |     Py_ssize_t n = Py_SIZE(deque); | 
 |     Py_ssize_t count = 0; | 
 |     size_t start_state = deque->state; | 
 |     PyObject *item; | 
 |     int cmp; | 
 |  | 
 |     while (--n >= 0) { | 
 |         CHECK_NOT_END(b); | 
 |         item = b->data[index]; | 
 |         cmp = PyObject_RichCompareBool(item, v, Py_EQ); | 
 |         if (cmp < 0) | 
 |             return NULL; | 
 |         count += cmp; | 
 |  | 
 |         if (start_state != deque->state) { | 
 |             PyErr_SetString(PyExc_RuntimeError, | 
 |                             "deque mutated during iteration"); | 
 |             return NULL; | 
 |         } | 
 |  | 
 |         /* Advance left block/index pair */ | 
 |         index++; | 
 |         if (index == BLOCKLEN) { | 
 |             b = b->rightlink; | 
 |             index = 0; | 
 |         } | 
 |     } | 
 |     return PyLong_FromSsize_t(count); | 
 | } | 
 |  | 
 | PyDoc_STRVAR(count_doc, | 
 | "D.count(value) -> integer -- return number of occurrences of value"); | 
 |  | 
 | static int | 
 | deque_contains(dequeobject *deque, PyObject *v) | 
 | { | 
 |     block *b = deque->leftblock; | 
 |     Py_ssize_t index = deque->leftindex; | 
 |     Py_ssize_t n = Py_SIZE(deque); | 
 |     size_t start_state = deque->state; | 
 |     PyObject *item; | 
 |     int cmp; | 
 |  | 
 |     while (--n >= 0) { | 
 |         CHECK_NOT_END(b); | 
 |         item = b->data[index]; | 
 |         cmp = PyObject_RichCompareBool(item, v, Py_EQ); | 
 |         if (cmp) { | 
 |             return cmp; | 
 |         } | 
 |         if (start_state != deque->state) { | 
 |             PyErr_SetString(PyExc_RuntimeError, | 
 |                             "deque mutated during iteration"); | 
 |             return -1; | 
 |         } | 
 |         index++; | 
 |         if (index == BLOCKLEN) { | 
 |             b = b->rightlink; | 
 |             index = 0; | 
 |         } | 
 |     } | 
 |     return 0; | 
 | } | 
 |  | 
 | static Py_ssize_t | 
 | deque_len(dequeobject *deque) | 
 | { | 
 |     return Py_SIZE(deque); | 
 | } | 
 |  | 
 | static PyObject * | 
 | deque_index(dequeobject *deque, PyObject *const *args, Py_ssize_t nargs) | 
 | { | 
 |     Py_ssize_t i, n, start=0, stop=Py_SIZE(deque); | 
 |     PyObject *v, *item; | 
 |     block *b = deque->leftblock; | 
 |     Py_ssize_t index = deque->leftindex; | 
 |     size_t start_state = deque->state; | 
 |     int cmp; | 
 |  | 
 |     if (!_PyArg_ParseStack(args, nargs, "O|O&O&:index", &v, | 
 |                            _PyEval_SliceIndexNotNone, &start, | 
 |                            _PyEval_SliceIndexNotNone, &stop)) { | 
 |         return NULL; | 
 |     } | 
 |  | 
 |     if (start < 0) { | 
 |         start += Py_SIZE(deque); | 
 |         if (start < 0) | 
 |             start = 0; | 
 |     } | 
 |     if (stop < 0) { | 
 |         stop += Py_SIZE(deque); | 
 |         if (stop < 0) | 
 |             stop = 0; | 
 |     } | 
 |     if (stop > Py_SIZE(deque)) | 
 |         stop = Py_SIZE(deque); | 
 |     if (start > stop) | 
 |         start = stop; | 
 |     assert(0 <= start && start <= stop && stop <= Py_SIZE(deque)); | 
 |  | 
 |     for (i=0 ; i < start - BLOCKLEN ; i += BLOCKLEN) { | 
 |         b = b->rightlink; | 
 |     } | 
 |     for ( ; i < start ; i++) { | 
 |         index++; | 
 |         if (index == BLOCKLEN) { | 
 |             b = b->rightlink; | 
 |             index = 0; | 
 |         } | 
 |     } | 
 |  | 
 |     n = stop - i; | 
 |     while (--n >= 0) { | 
 |         CHECK_NOT_END(b); | 
 |         item = b->data[index]; | 
 |         cmp = PyObject_RichCompareBool(item, v, Py_EQ); | 
 |         if (cmp > 0) | 
 |             return PyLong_FromSsize_t(stop - n - 1); | 
 |         if (cmp < 0) | 
 |             return NULL; | 
 |         if (start_state != deque->state) { | 
 |             PyErr_SetString(PyExc_RuntimeError, | 
 |                             "deque mutated during iteration"); | 
 |             return NULL; | 
 |         } | 
 |         index++; | 
 |         if (index == BLOCKLEN) { | 
 |             b = b->rightlink; | 
 |             index = 0; | 
 |         } | 
 |     } | 
 |     PyErr_Format(PyExc_ValueError, "%R is not in deque", v); | 
 |     return NULL; | 
 | } | 
 |  | 
 | PyDoc_STRVAR(index_doc, | 
 | "D.index(value, [start, [stop]]) -> integer -- return first index of value.\n" | 
 | "Raises ValueError if the value is not present."); | 
 |  | 
 | /* insert(), remove(), and delitem() are implemented in terms of | 
 |    rotate() for simplicity and reasonable performance near the end | 
 |    points.  If for some reason these methods become popular, it is not | 
 |    hard to re-implement this using direct data movement (similar to | 
 |    the code used in list slice assignments) and achieve a performance | 
 |    boost (by moving each pointer only once instead of twice). | 
 | */ | 
 |  | 
 | static PyObject * | 
 | deque_insert(dequeobject *deque, PyObject *const *args, Py_ssize_t nargs) | 
 | { | 
 |     Py_ssize_t index; | 
 |     Py_ssize_t n = Py_SIZE(deque); | 
 |     PyObject *value; | 
 |     PyObject *rv; | 
 |  | 
 |     if (!_PyArg_ParseStack(args, nargs, "nO:insert", &index, &value)) { | 
 |         return NULL; | 
 |     } | 
 |  | 
 |     if (deque->maxlen == Py_SIZE(deque)) { | 
 |         PyErr_SetString(PyExc_IndexError, "deque already at its maximum size"); | 
 |         return NULL; | 
 |     } | 
 |     if (index >= n) | 
 |         return deque_append(deque, value); | 
 |     if (index <= -n || index == 0) | 
 |         return deque_appendleft(deque, value); | 
 |     if (_deque_rotate(deque, -index)) | 
 |         return NULL; | 
 |     if (index < 0) | 
 |         rv = deque_append(deque, value); | 
 |     else | 
 |         rv = deque_appendleft(deque, value); | 
 |     if (rv == NULL) | 
 |         return NULL; | 
 |     Py_DECREF(rv); | 
 |     if (_deque_rotate(deque, index)) | 
 |         return NULL; | 
 |     Py_RETURN_NONE; | 
 | } | 
 |  | 
 | PyDoc_STRVAR(insert_doc, | 
 | "D.insert(index, object) -- insert object before index"); | 
 |  | 
 | static PyObject * | 
 | deque_remove(dequeobject *deque, PyObject *value) | 
 | { | 
 |     Py_ssize_t i, n=Py_SIZE(deque); | 
 |  | 
 |     for (i=0 ; i<n ; i++) { | 
 |         PyObject *item = deque->leftblock->data[deque->leftindex]; | 
 |         int cmp = PyObject_RichCompareBool(item, value, Py_EQ); | 
 |  | 
 |         if (Py_SIZE(deque) != n) { | 
 |             PyErr_SetString(PyExc_IndexError, | 
 |                 "deque mutated during remove()."); | 
 |             return NULL; | 
 |         } | 
 |         if (cmp > 0) { | 
 |             PyObject *tgt = deque_popleft(deque, NULL); | 
 |             assert (tgt != NULL); | 
 |             if (_deque_rotate(deque, i)) | 
 |                 return NULL; | 
 |             Py_DECREF(tgt); | 
 |             Py_RETURN_NONE; | 
 |         } | 
 |         else if (cmp < 0) { | 
 |             _deque_rotate(deque, i); | 
 |             return NULL; | 
 |         } | 
 |         _deque_rotate(deque, -1); | 
 |     } | 
 |     PyErr_SetString(PyExc_ValueError, "deque.remove(x): x not in deque"); | 
 |     return NULL; | 
 | } | 
 |  | 
 | PyDoc_STRVAR(remove_doc, | 
 | "D.remove(value) -- remove first occurrence of value."); | 
 |  | 
 | static int | 
 | valid_index(Py_ssize_t i, Py_ssize_t limit) | 
 | { | 
 |     /* The cast to size_t lets us use just a single comparison | 
 |        to check whether i is in the range: 0 <= i < limit */ | 
 |     return (size_t) i < (size_t) limit; | 
 | } | 
 |  | 
 | static PyObject * | 
 | deque_item(dequeobject *deque, Py_ssize_t i) | 
 | { | 
 |     block *b; | 
 |     PyObject *item; | 
 |     Py_ssize_t n, index=i; | 
 |  | 
 |     if (!valid_index(i, Py_SIZE(deque))) { | 
 |         PyErr_SetString(PyExc_IndexError, "deque index out of range"); | 
 |         return NULL; | 
 |     } | 
 |  | 
 |     if (i == 0) { | 
 |         i = deque->leftindex; | 
 |         b = deque->leftblock; | 
 |     } else if (i == Py_SIZE(deque) - 1) { | 
 |         i = deque->rightindex; | 
 |         b = deque->rightblock; | 
 |     } else { | 
 |         i += deque->leftindex; | 
 |         n = (Py_ssize_t)((size_t) i / BLOCKLEN); | 
 |         i = (Py_ssize_t)((size_t) i % BLOCKLEN); | 
 |         if (index < (Py_SIZE(deque) >> 1)) { | 
 |             b = deque->leftblock; | 
 |             while (--n >= 0) | 
 |                 b = b->rightlink; | 
 |         } else { | 
 |             n = (Py_ssize_t)( | 
 |                     ((size_t)(deque->leftindex + Py_SIZE(deque) - 1)) | 
 |                     / BLOCKLEN - n); | 
 |             b = deque->rightblock; | 
 |             while (--n >= 0) | 
 |                 b = b->leftlink; | 
 |         } | 
 |     } | 
 |     item = b->data[i]; | 
 |     Py_INCREF(item); | 
 |     return item; | 
 | } | 
 |  | 
 | static int | 
 | deque_del_item(dequeobject *deque, Py_ssize_t i) | 
 | { | 
 |     PyObject *item; | 
 |     int rv; | 
 |  | 
 |     assert (i >= 0 && i < Py_SIZE(deque)); | 
 |     if (_deque_rotate(deque, -i)) | 
 |         return -1; | 
 |     item = deque_popleft(deque, NULL); | 
 |     rv = _deque_rotate(deque, i); | 
 |     assert (item != NULL); | 
 |     Py_DECREF(item); | 
 |     return rv; | 
 | } | 
 |  | 
 | static int | 
 | deque_ass_item(dequeobject *deque, Py_ssize_t i, PyObject *v) | 
 | { | 
 |     PyObject *old_value; | 
 |     block *b; | 
 |     Py_ssize_t n, len=Py_SIZE(deque), halflen=(len+1)>>1, index=i; | 
 |  | 
 |     if (!valid_index(i, len)) { | 
 |         PyErr_SetString(PyExc_IndexError, "deque index out of range"); | 
 |         return -1; | 
 |     } | 
 |     if (v == NULL) | 
 |         return deque_del_item(deque, i); | 
 |  | 
 |     i += deque->leftindex; | 
 |     n = (Py_ssize_t)((size_t) i / BLOCKLEN); | 
 |     i = (Py_ssize_t)((size_t) i % BLOCKLEN); | 
 |     if (index <= halflen) { | 
 |         b = deque->leftblock; | 
 |         while (--n >= 0) | 
 |             b = b->rightlink; | 
 |     } else { | 
 |         n = (Py_ssize_t)( | 
 |                 ((size_t)(deque->leftindex + Py_SIZE(deque) - 1)) | 
 |                 / BLOCKLEN - n); | 
 |         b = deque->rightblock; | 
 |         while (--n >= 0) | 
 |             b = b->leftlink; | 
 |     } | 
 |     Py_INCREF(v); | 
 |     old_value = b->data[i]; | 
 |     b->data[i] = v; | 
 |     Py_DECREF(old_value); | 
 |     return 0; | 
 | } | 
 |  | 
 | static void | 
 | deque_dealloc(dequeobject *deque) | 
 | { | 
 |     PyObject_GC_UnTrack(deque); | 
 |     if (deque->weakreflist != NULL) | 
 |         PyObject_ClearWeakRefs((PyObject *) deque); | 
 |     if (deque->leftblock != NULL) { | 
 |         deque_clear(deque); | 
 |         assert(deque->leftblock != NULL); | 
 |         freeblock(deque->leftblock); | 
 |     } | 
 |     deque->leftblock = NULL; | 
 |     deque->rightblock = NULL; | 
 |     Py_TYPE(deque)->tp_free(deque); | 
 | } | 
 |  | 
 | static int | 
 | deque_traverse(dequeobject *deque, visitproc visit, void *arg) | 
 | { | 
 |     block *b; | 
 |     PyObject *item; | 
 |     Py_ssize_t index; | 
 |     Py_ssize_t indexlo = deque->leftindex; | 
 |     Py_ssize_t indexhigh; | 
 |  | 
 |     for (b = deque->leftblock; b != deque->rightblock; b = b->rightlink) { | 
 |         for (index = indexlo; index < BLOCKLEN ; index++) { | 
 |             item = b->data[index]; | 
 |             Py_VISIT(item); | 
 |         } | 
 |         indexlo = 0; | 
 |     } | 
 |     indexhigh = deque->rightindex; | 
 |     for (index = indexlo; index <= indexhigh; index++) { | 
 |         item = b->data[index]; | 
 |         Py_VISIT(item); | 
 |     } | 
 |     return 0; | 
 | } | 
 |  | 
 | static PyObject * | 
 | deque_reduce(dequeobject *deque, PyObject *Py_UNUSED(ignored)) | 
 | { | 
 |     PyObject *dict, *it; | 
 |     _Py_IDENTIFIER(__dict__); | 
 |  | 
 |     if (_PyObject_LookupAttrId((PyObject *)deque, &PyId___dict__, &dict) < 0) { | 
 |         return NULL; | 
 |     } | 
 |     if (dict == NULL) { | 
 |         dict = Py_None; | 
 |         Py_INCREF(dict); | 
 |     } | 
 |  | 
 |     it = PyObject_GetIter((PyObject *)deque); | 
 |     if (it == NULL) { | 
 |         Py_DECREF(dict); | 
 |         return NULL; | 
 |     } | 
 |  | 
 |     if (deque->maxlen < 0) { | 
 |         return Py_BuildValue("O()NN", Py_TYPE(deque), dict, it); | 
 |     } | 
 |     else { | 
 |         return Py_BuildValue("O(()n)NN", Py_TYPE(deque), deque->maxlen, dict, it); | 
 |     } | 
 | } | 
 |  | 
 | PyDoc_STRVAR(reduce_doc, "Return state information for pickling."); | 
 |  | 
 | static PyObject * | 
 | deque_repr(PyObject *deque) | 
 | { | 
 |     PyObject *aslist, *result; | 
 |     int i; | 
 |  | 
 |     i = Py_ReprEnter(deque); | 
 |     if (i != 0) { | 
 |         if (i < 0) | 
 |             return NULL; | 
 |         return PyUnicode_FromString("[...]"); | 
 |     } | 
 |  | 
 |     aslist = PySequence_List(deque); | 
 |     if (aslist == NULL) { | 
 |         Py_ReprLeave(deque); | 
 |         return NULL; | 
 |     } | 
 |     if (((dequeobject *)deque)->maxlen >= 0) | 
 |         result = PyUnicode_FromFormat("%s(%R, maxlen=%zd)", | 
 |                                       _PyType_Name(Py_TYPE(deque)), aslist, | 
 |                                       ((dequeobject *)deque)->maxlen); | 
 |     else | 
 |         result = PyUnicode_FromFormat("%s(%R)", | 
 |                                       _PyType_Name(Py_TYPE(deque)), aslist); | 
 |     Py_ReprLeave(deque); | 
 |     Py_DECREF(aslist); | 
 |     return result; | 
 | } | 
 |  | 
 | static PyObject * | 
 | deque_richcompare(PyObject *v, PyObject *w, int op) | 
 | { | 
 |     PyObject *it1=NULL, *it2=NULL, *x, *y; | 
 |     Py_ssize_t vs, ws; | 
 |     int b, cmp=-1; | 
 |  | 
 |     if (!PyObject_TypeCheck(v, &deque_type) || | 
 |         !PyObject_TypeCheck(w, &deque_type)) { | 
 |         Py_RETURN_NOTIMPLEMENTED; | 
 |     } | 
 |  | 
 |     /* Shortcuts */ | 
 |     vs = Py_SIZE((dequeobject *)v); | 
 |     ws = Py_SIZE((dequeobject *)w); | 
 |     if (op == Py_EQ) { | 
 |         if (v == w) | 
 |             Py_RETURN_TRUE; | 
 |         if (vs != ws) | 
 |             Py_RETURN_FALSE; | 
 |     } | 
 |     if (op == Py_NE) { | 
 |         if (v == w) | 
 |             Py_RETURN_FALSE; | 
 |         if (vs != ws) | 
 |             Py_RETURN_TRUE; | 
 |     } | 
 |  | 
 |     /* Search for the first index where items are different */ | 
 |     it1 = PyObject_GetIter(v); | 
 |     if (it1 == NULL) | 
 |         goto done; | 
 |     it2 = PyObject_GetIter(w); | 
 |     if (it2 == NULL) | 
 |         goto done; | 
 |     for (;;) { | 
 |         x = PyIter_Next(it1); | 
 |         if (x == NULL && PyErr_Occurred()) | 
 |             goto done; | 
 |         y = PyIter_Next(it2); | 
 |         if (x == NULL || y == NULL) | 
 |             break; | 
 |         b = PyObject_RichCompareBool(x, y, Py_EQ); | 
 |         if (b == 0) { | 
 |             cmp = PyObject_RichCompareBool(x, y, op); | 
 |             Py_DECREF(x); | 
 |             Py_DECREF(y); | 
 |             goto done; | 
 |         } | 
 |         Py_DECREF(x); | 
 |         Py_DECREF(y); | 
 |         if (b < 0) | 
 |             goto done; | 
 |     } | 
 |     /* We reached the end of one deque or both */ | 
 |     Py_XDECREF(x); | 
 |     Py_XDECREF(y); | 
 |     if (PyErr_Occurred()) | 
 |         goto done; | 
 |     switch (op) { | 
 |     case Py_LT: cmp = y != NULL; break;  /* if w was longer */ | 
 |     case Py_LE: cmp = x == NULL; break;  /* if v was not longer */ | 
 |     case Py_EQ: cmp = x == y;    break;  /* if we reached the end of both */ | 
 |     case Py_NE: cmp = x != y;    break;  /* if one deque continues */ | 
 |     case Py_GT: cmp = x != NULL; break;  /* if v was longer */ | 
 |     case Py_GE: cmp = y == NULL; break;  /* if w was not longer */ | 
 |     } | 
 |  | 
 | done: | 
 |     Py_XDECREF(it1); | 
 |     Py_XDECREF(it2); | 
 |     if (cmp == 1) | 
 |         Py_RETURN_TRUE; | 
 |     if (cmp == 0) | 
 |         Py_RETURN_FALSE; | 
 |     return NULL; | 
 | } | 
 |  | 
 | static int | 
 | deque_init(dequeobject *deque, PyObject *args, PyObject *kwdargs) | 
 | { | 
 |     PyObject *iterable = NULL; | 
 |     PyObject *maxlenobj = NULL; | 
 |     Py_ssize_t maxlen = -1; | 
 |     char *kwlist[] = {"iterable", "maxlen", 0}; | 
 |  | 
 |     if (kwdargs == NULL && PyTuple_GET_SIZE(args) <= 2) { | 
 |         if (PyTuple_GET_SIZE(args) > 0) { | 
 |             iterable = PyTuple_GET_ITEM(args, 0); | 
 |         } | 
 |         if (PyTuple_GET_SIZE(args) > 1) { | 
 |             maxlenobj = PyTuple_GET_ITEM(args, 1); | 
 |         } | 
 |     } else { | 
 |         if (!PyArg_ParseTupleAndKeywords(args, kwdargs, "|OO:deque", kwlist, | 
 |                                          &iterable, &maxlenobj)) | 
 |             return -1; | 
 |     } | 
 |     if (maxlenobj != NULL && maxlenobj != Py_None) { | 
 |         maxlen = PyLong_AsSsize_t(maxlenobj); | 
 |         if (maxlen == -1 && PyErr_Occurred()) | 
 |             return -1; | 
 |         if (maxlen < 0) { | 
 |             PyErr_SetString(PyExc_ValueError, "maxlen must be non-negative"); | 
 |             return -1; | 
 |         } | 
 |     } | 
 |     deque->maxlen = maxlen; | 
 |     if (Py_SIZE(deque) > 0) | 
 |         deque_clear(deque); | 
 |     if (iterable != NULL) { | 
 |         PyObject *rv = deque_extend(deque, iterable); | 
 |         if (rv == NULL) | 
 |             return -1; | 
 |         Py_DECREF(rv); | 
 |     } | 
 |     return 0; | 
 | } | 
 |  | 
 | static PyObject * | 
 | deque_sizeof(dequeobject *deque, void *unused) | 
 | { | 
 |     Py_ssize_t res; | 
 |     Py_ssize_t blocks; | 
 |  | 
 |     res = _PyObject_SIZE(Py_TYPE(deque)); | 
 |     blocks = (size_t)(deque->leftindex + Py_SIZE(deque) + BLOCKLEN - 1) / BLOCKLEN; | 
 |     assert(deque->leftindex + Py_SIZE(deque) - 1 == | 
 |            (blocks - 1) * BLOCKLEN + deque->rightindex); | 
 |     res += blocks * sizeof(block); | 
 |     return PyLong_FromSsize_t(res); | 
 | } | 
 |  | 
 | PyDoc_STRVAR(sizeof_doc, | 
 | "D.__sizeof__() -- size of D in memory, in bytes"); | 
 |  | 
 | static int | 
 | deque_bool(dequeobject *deque) | 
 | { | 
 |     return Py_SIZE(deque) != 0; | 
 | } | 
 |  | 
 | static PyObject * | 
 | deque_get_maxlen(dequeobject *deque, void *Py_UNUSED(ignored)) | 
 | { | 
 |     if (deque->maxlen < 0) | 
 |         Py_RETURN_NONE; | 
 |     return PyLong_FromSsize_t(deque->maxlen); | 
 | } | 
 |  | 
 |  | 
 | /* deque object ********************************************************/ | 
 |  | 
 | static PyGetSetDef deque_getset[] = { | 
 |     {"maxlen", (getter)deque_get_maxlen, (setter)NULL, | 
 |      "maximum size of a deque or None if unbounded"}, | 
 |     {0} | 
 | }; | 
 |  | 
 | static PySequenceMethods deque_as_sequence = { | 
 |     (lenfunc)deque_len,                 /* sq_length */ | 
 |     (binaryfunc)deque_concat,           /* sq_concat */ | 
 |     (ssizeargfunc)deque_repeat,         /* sq_repeat */ | 
 |     (ssizeargfunc)deque_item,           /* sq_item */ | 
 |     0,                                  /* sq_slice */ | 
 |     (ssizeobjargproc)deque_ass_item,    /* sq_ass_item */ | 
 |     0,                                  /* sq_ass_slice */ | 
 |     (objobjproc)deque_contains,         /* sq_contains */ | 
 |     (binaryfunc)deque_inplace_concat,   /* sq_inplace_concat */ | 
 |     (ssizeargfunc)deque_inplace_repeat, /* sq_inplace_repeat */ | 
 | }; | 
 |  | 
 | static PyNumberMethods deque_as_number = { | 
 |     0,                                  /* nb_add */ | 
 |     0,                                  /* nb_subtract */ | 
 |     0,                                  /* nb_multiply */ | 
 |     0,                                  /* nb_remainder */ | 
 |     0,                                  /* nb_divmod */ | 
 |     0,                                  /* nb_power */ | 
 |     0,                                  /* nb_negative */ | 
 |     0,                                  /* nb_positive */ | 
 |     0,                                  /* nb_absolute */ | 
 |     (inquiry)deque_bool,                /* nb_bool */ | 
 |     0,                                  /* nb_invert */ | 
 |  }; | 
 |  | 
 | static PyObject *deque_iter(dequeobject *deque); | 
 | static PyObject *deque_reviter(dequeobject *deque, PyObject *Py_UNUSED(ignored)); | 
 | PyDoc_STRVAR(reversed_doc, | 
 |     "D.__reversed__() -- return a reverse iterator over the deque"); | 
 |  | 
 | static PyMethodDef deque_methods[] = { | 
 |     {"append",                  (PyCFunction)deque_append, | 
 |         METH_O,                  append_doc}, | 
 |     {"appendleft",              (PyCFunction)deque_appendleft, | 
 |         METH_O,                  appendleft_doc}, | 
 |     {"clear",                   (PyCFunction)deque_clearmethod, | 
 |         METH_NOARGS,             clear_doc}, | 
 |     {"__copy__",                deque_copy, | 
 |         METH_NOARGS,             copy_doc}, | 
 |     {"copy",                    deque_copy, | 
 |         METH_NOARGS,             copy_doc}, | 
 |     {"count",                   (PyCFunction)deque_count, | 
 |         METH_O,                  count_doc}, | 
 |     {"extend",                  (PyCFunction)deque_extend, | 
 |         METH_O,                  extend_doc}, | 
 |     {"extendleft",              (PyCFunction)deque_extendleft, | 
 |         METH_O,                  extendleft_doc}, | 
 |     {"index",                   (PyCFunction)(void(*)(void))deque_index, | 
 |         METH_FASTCALL,            index_doc}, | 
 |     {"insert",                  (PyCFunction)(void(*)(void))deque_insert, | 
 |         METH_FASTCALL,            insert_doc}, | 
 |     {"pop",                     (PyCFunction)deque_pop, | 
 |         METH_NOARGS,             pop_doc}, | 
 |     {"popleft",                 (PyCFunction)deque_popleft, | 
 |         METH_NOARGS,             popleft_doc}, | 
 |     {"__reduce__",              (PyCFunction)deque_reduce, | 
 |         METH_NOARGS,             reduce_doc}, | 
 |     {"remove",                  (PyCFunction)deque_remove, | 
 |         METH_O,                  remove_doc}, | 
 |     {"__reversed__",            (PyCFunction)deque_reviter, | 
 |         METH_NOARGS,             reversed_doc}, | 
 |     {"reverse",                 (PyCFunction)deque_reverse, | 
 |         METH_NOARGS,             reverse_doc}, | 
 |     {"rotate",                  (PyCFunction)(void(*)(void))deque_rotate, | 
 |         METH_FASTCALL,            rotate_doc}, | 
 |     {"__sizeof__",              (PyCFunction)deque_sizeof, | 
 |         METH_NOARGS,             sizeof_doc}, | 
 |     {NULL,              NULL}   /* sentinel */ | 
 | }; | 
 |  | 
 | PyDoc_STRVAR(deque_doc, | 
 | "deque([iterable[, maxlen]]) --> deque object\n\ | 
 | \n\ | 
 | A list-like sequence optimized for data accesses near its endpoints."); | 
 |  | 
 | static PyTypeObject deque_type = { | 
 |     PyVarObject_HEAD_INIT(NULL, 0) | 
 |     "collections.deque",                /* tp_name */ | 
 |     sizeof(dequeobject),                /* tp_basicsize */ | 
 |     0,                                  /* tp_itemsize */ | 
 |     /* methods */ | 
 |     (destructor)deque_dealloc,          /* tp_dealloc */ | 
 |     0,                                  /* tp_vectorcall_offset */ | 
 |     0,                                  /* tp_getattr */ | 
 |     0,                                  /* tp_setattr */ | 
 |     0,                                  /* tp_as_async */ | 
 |     deque_repr,                         /* tp_repr */ | 
 |     &deque_as_number,                   /* tp_as_number */ | 
 |     &deque_as_sequence,                 /* tp_as_sequence */ | 
 |     0,                                  /* tp_as_mapping */ | 
 |     PyObject_HashNotImplemented,        /* tp_hash */ | 
 |     0,                                  /* tp_call */ | 
 |     0,                                  /* tp_str */ | 
 |     PyObject_GenericGetAttr,            /* tp_getattro */ | 
 |     0,                                  /* tp_setattro */ | 
 |     0,                                  /* tp_as_buffer */ | 
 |     Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_GC, | 
 |                                         /* tp_flags */ | 
 |     deque_doc,                          /* tp_doc */ | 
 |     (traverseproc)deque_traverse,       /* tp_traverse */ | 
 |     (inquiry)deque_clear,               /* tp_clear */ | 
 |     (richcmpfunc)deque_richcompare,     /* tp_richcompare */ | 
 |     offsetof(dequeobject, weakreflist), /* tp_weaklistoffset*/ | 
 |     (getiterfunc)deque_iter,            /* tp_iter */ | 
 |     0,                                  /* tp_iternext */ | 
 |     deque_methods,                      /* tp_methods */ | 
 |     0,                                  /* tp_members */ | 
 |     deque_getset,                       /* tp_getset */ | 
 |     0,                                  /* tp_base */ | 
 |     0,                                  /* tp_dict */ | 
 |     0,                                  /* tp_descr_get */ | 
 |     0,                                  /* tp_descr_set */ | 
 |     0,                                  /* tp_dictoffset */ | 
 |     (initproc)deque_init,               /* tp_init */ | 
 |     PyType_GenericAlloc,                /* tp_alloc */ | 
 |     deque_new,                          /* tp_new */ | 
 |     PyObject_GC_Del,                    /* tp_free */ | 
 | }; | 
 |  | 
 | /*********************** Deque Iterator **************************/ | 
 |  | 
 | typedef struct { | 
 |     PyObject_HEAD | 
 |     block *b; | 
 |     Py_ssize_t index; | 
 |     dequeobject *deque; | 
 |     size_t state;          /* state when the iterator is created */ | 
 |     Py_ssize_t counter;    /* number of items remaining for iteration */ | 
 | } dequeiterobject; | 
 |  | 
 | static PyTypeObject dequeiter_type; | 
 |  | 
 | static PyObject * | 
 | deque_iter(dequeobject *deque) | 
 | { | 
 |     dequeiterobject *it; | 
 |  | 
 |     it = PyObject_GC_New(dequeiterobject, &dequeiter_type); | 
 |     if (it == NULL) | 
 |         return NULL; | 
 |     it->b = deque->leftblock; | 
 |     it->index = deque->leftindex; | 
 |     Py_INCREF(deque); | 
 |     it->deque = deque; | 
 |     it->state = deque->state; | 
 |     it->counter = Py_SIZE(deque); | 
 |     PyObject_GC_Track(it); | 
 |     return (PyObject *)it; | 
 | } | 
 |  | 
 | static int | 
 | dequeiter_traverse(dequeiterobject *dio, visitproc visit, void *arg) | 
 | { | 
 |     Py_VISIT(dio->deque); | 
 |     return 0; | 
 | } | 
 |  | 
 | static void | 
 | dequeiter_dealloc(dequeiterobject *dio) | 
 | { | 
 |     /* bpo-31095: UnTrack is needed before calling any callbacks */ | 
 |     PyObject_GC_UnTrack(dio); | 
 |     Py_XDECREF(dio->deque); | 
 |     PyObject_GC_Del(dio); | 
 | } | 
 |  | 
 | static PyObject * | 
 | dequeiter_next(dequeiterobject *it) | 
 | { | 
 |     PyObject *item; | 
 |  | 
 |     if (it->deque->state != it->state) { | 
 |         it->counter = 0; | 
 |         PyErr_SetString(PyExc_RuntimeError, | 
 |                         "deque mutated during iteration"); | 
 |         return NULL; | 
 |     } | 
 |     if (it->counter == 0) | 
 |         return NULL; | 
 |     assert (!(it->b == it->deque->rightblock && | 
 |               it->index > it->deque->rightindex)); | 
 |  | 
 |     item = it->b->data[it->index]; | 
 |     it->index++; | 
 |     it->counter--; | 
 |     if (it->index == BLOCKLEN && it->counter > 0) { | 
 |         CHECK_NOT_END(it->b->rightlink); | 
 |         it->b = it->b->rightlink; | 
 |         it->index = 0; | 
 |     } | 
 |     Py_INCREF(item); | 
 |     return item; | 
 | } | 
 |  | 
 | static PyObject * | 
 | dequeiter_new(PyTypeObject *type, PyObject *args, PyObject *kwds) | 
 | { | 
 |     Py_ssize_t i, index=0; | 
 |     PyObject *deque; | 
 |     dequeiterobject *it; | 
 |     if (!PyArg_ParseTuple(args, "O!|n", &deque_type, &deque, &index)) | 
 |         return NULL; | 
 |     assert(type == &dequeiter_type); | 
 |  | 
 |     it = (dequeiterobject*)deque_iter((dequeobject *)deque); | 
 |     if (!it) | 
 |         return NULL; | 
 |     /* consume items from the queue */ | 
 |     for(i=0; i<index; i++) { | 
 |         PyObject *item = dequeiter_next(it); | 
 |         if (item) { | 
 |             Py_DECREF(item); | 
 |         } else { | 
 |             if (it->counter) { | 
 |                 Py_DECREF(it); | 
 |                 return NULL; | 
 |             } else | 
 |                 break; | 
 |         } | 
 |     } | 
 |     return (PyObject*)it; | 
 | } | 
 |  | 
 | static PyObject * | 
 | dequeiter_len(dequeiterobject *it, PyObject *Py_UNUSED(ignored)) | 
 | { | 
 |     return PyLong_FromSsize_t(it->counter); | 
 | } | 
 |  | 
 | PyDoc_STRVAR(length_hint_doc, "Private method returning an estimate of len(list(it))."); | 
 |  | 
 | static PyObject * | 
 | dequeiter_reduce(dequeiterobject *it, PyObject *Py_UNUSED(ignored)) | 
 | { | 
 |     return Py_BuildValue("O(On)", Py_TYPE(it), it->deque, Py_SIZE(it->deque) - it->counter); | 
 | } | 
 |  | 
 | static PyMethodDef dequeiter_methods[] = { | 
 |     {"__length_hint__", (PyCFunction)dequeiter_len, METH_NOARGS, length_hint_doc}, | 
 |     {"__reduce__", (PyCFunction)dequeiter_reduce, METH_NOARGS, reduce_doc}, | 
 |     {NULL,              NULL}           /* sentinel */ | 
 | }; | 
 |  | 
 | static PyTypeObject dequeiter_type = { | 
 |     PyVarObject_HEAD_INIT(NULL, 0) | 
 |     "_collections._deque_iterator",             /* tp_name */ | 
 |     sizeof(dequeiterobject),                    /* tp_basicsize */ | 
 |     0,                                          /* tp_itemsize */ | 
 |     /* methods */ | 
 |     (destructor)dequeiter_dealloc,              /* tp_dealloc */ | 
 |     0,                                          /* tp_vectorcall_offset */ | 
 |     0,                                          /* tp_getattr */ | 
 |     0,                                          /* tp_setattr */ | 
 |     0,                                          /* tp_as_async */ | 
 |     0,                                          /* tp_repr */ | 
 |     0,                                          /* tp_as_number */ | 
 |     0,                                          /* tp_as_sequence */ | 
 |     0,                                          /* tp_as_mapping */ | 
 |     0,                                          /* tp_hash */ | 
 |     0,                                          /* tp_call */ | 
 |     0,                                          /* tp_str */ | 
 |     PyObject_GenericGetAttr,                    /* tp_getattro */ | 
 |     0,                                          /* tp_setattro */ | 
 |     0,                                          /* tp_as_buffer */ | 
 |     Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,    /* tp_flags */ | 
 |     0,                                          /* tp_doc */ | 
 |     (traverseproc)dequeiter_traverse,           /* tp_traverse */ | 
 |     0,                                          /* tp_clear */ | 
 |     0,                                          /* tp_richcompare */ | 
 |     0,                                          /* tp_weaklistoffset */ | 
 |     PyObject_SelfIter,                          /* tp_iter */ | 
 |     (iternextfunc)dequeiter_next,               /* tp_iternext */ | 
 |     dequeiter_methods,                          /* tp_methods */ | 
 |     0,                                          /* tp_members */ | 
 |     0,                                          /* tp_getset */ | 
 |     0,                                          /* tp_base */ | 
 |     0,                                          /* tp_dict */ | 
 |     0,                                          /* tp_descr_get */ | 
 |     0,                                          /* tp_descr_set */ | 
 |     0,                                          /* tp_dictoffset */ | 
 |     0,                                          /* tp_init */ | 
 |     0,                                          /* tp_alloc */ | 
 |     dequeiter_new,                              /* tp_new */ | 
 |     0, | 
 | }; | 
 |  | 
 | /*********************** Deque Reverse Iterator **************************/ | 
 |  | 
 | static PyTypeObject dequereviter_type; | 
 |  | 
 | static PyObject * | 
 | deque_reviter(dequeobject *deque, PyObject *Py_UNUSED(ignored)) | 
 | { | 
 |     dequeiterobject *it; | 
 |  | 
 |     it = PyObject_GC_New(dequeiterobject, &dequereviter_type); | 
 |     if (it == NULL) | 
 |         return NULL; | 
 |     it->b = deque->rightblock; | 
 |     it->index = deque->rightindex; | 
 |     Py_INCREF(deque); | 
 |     it->deque = deque; | 
 |     it->state = deque->state; | 
 |     it->counter = Py_SIZE(deque); | 
 |     PyObject_GC_Track(it); | 
 |     return (PyObject *)it; | 
 | } | 
 |  | 
 | static PyObject * | 
 | dequereviter_next(dequeiterobject *it) | 
 | { | 
 |     PyObject *item; | 
 |     if (it->counter == 0) | 
 |         return NULL; | 
 |  | 
 |     if (it->deque->state != it->state) { | 
 |         it->counter = 0; | 
 |         PyErr_SetString(PyExc_RuntimeError, | 
 |                         "deque mutated during iteration"); | 
 |         return NULL; | 
 |     } | 
 |     assert (!(it->b == it->deque->leftblock && | 
 |               it->index < it->deque->leftindex)); | 
 |  | 
 |     item = it->b->data[it->index]; | 
 |     it->index--; | 
 |     it->counter--; | 
 |     if (it->index < 0 && it->counter > 0) { | 
 |         CHECK_NOT_END(it->b->leftlink); | 
 |         it->b = it->b->leftlink; | 
 |         it->index = BLOCKLEN - 1; | 
 |     } | 
 |     Py_INCREF(item); | 
 |     return item; | 
 | } | 
 |  | 
 | static PyObject * | 
 | dequereviter_new(PyTypeObject *type, PyObject *args, PyObject *kwds) | 
 | { | 
 |     Py_ssize_t i, index=0; | 
 |     PyObject *deque; | 
 |     dequeiterobject *it; | 
 |     if (!PyArg_ParseTuple(args, "O!|n", &deque_type, &deque, &index)) | 
 |         return NULL; | 
 |     assert(type == &dequereviter_type); | 
 |  | 
 |     it = (dequeiterobject*)deque_reviter((dequeobject *)deque, NULL); | 
 |     if (!it) | 
 |         return NULL; | 
 |     /* consume items from the queue */ | 
 |     for(i=0; i<index; i++) { | 
 |         PyObject *item = dequereviter_next(it); | 
 |         if (item) { | 
 |             Py_DECREF(item); | 
 |         } else { | 
 |             if (it->counter) { | 
 |                 Py_DECREF(it); | 
 |                 return NULL; | 
 |             } else | 
 |                 break; | 
 |         } | 
 |     } | 
 |     return (PyObject*)it; | 
 | } | 
 |  | 
 | static PyTypeObject dequereviter_type = { | 
 |     PyVarObject_HEAD_INIT(NULL, 0) | 
 |     "_collections._deque_reverse_iterator",     /* tp_name */ | 
 |     sizeof(dequeiterobject),                    /* tp_basicsize */ | 
 |     0,                                          /* tp_itemsize */ | 
 |     /* methods */ | 
 |     (destructor)dequeiter_dealloc,              /* tp_dealloc */ | 
 |     0,                                          /* tp_vectorcall_offset */ | 
 |     0,                                          /* tp_getattr */ | 
 |     0,                                          /* tp_setattr */ | 
 |     0,                                          /* tp_as_async */ | 
 |     0,                                          /* tp_repr */ | 
 |     0,                                          /* tp_as_number */ | 
 |     0,                                          /* tp_as_sequence */ | 
 |     0,                                          /* tp_as_mapping */ | 
 |     0,                                          /* tp_hash */ | 
 |     0,                                          /* tp_call */ | 
 |     0,                                          /* tp_str */ | 
 |     PyObject_GenericGetAttr,                    /* tp_getattro */ | 
 |     0,                                          /* tp_setattro */ | 
 |     0,                                          /* tp_as_buffer */ | 
 |     Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,    /* tp_flags */ | 
 |     0,                                          /* tp_doc */ | 
 |     (traverseproc)dequeiter_traverse,           /* tp_traverse */ | 
 |     0,                                          /* tp_clear */ | 
 |     0,                                          /* tp_richcompare */ | 
 |     0,                                          /* tp_weaklistoffset */ | 
 |     PyObject_SelfIter,                          /* tp_iter */ | 
 |     (iternextfunc)dequereviter_next,            /* tp_iternext */ | 
 |     dequeiter_methods,                          /* tp_methods */ | 
 |     0,                                          /* tp_members */ | 
 |     0,                                          /* tp_getset */ | 
 |     0,                                          /* tp_base */ | 
 |     0,                                          /* tp_dict */ | 
 |     0,                                          /* tp_descr_get */ | 
 |     0,                                          /* tp_descr_set */ | 
 |     0,                                          /* tp_dictoffset */ | 
 |     0,                                          /* tp_init */ | 
 |     0,                                          /* tp_alloc */ | 
 |     dequereviter_new,                           /* tp_new */ | 
 |     0, | 
 | }; | 
 |  | 
 | /* defaultdict type *********************************************************/ | 
 |  | 
 | typedef struct { | 
 |     PyDictObject dict; | 
 |     PyObject *default_factory; | 
 | } defdictobject; | 
 |  | 
 | static PyTypeObject defdict_type; /* Forward */ | 
 |  | 
 | PyDoc_STRVAR(defdict_missing_doc, | 
 | "__missing__(key) # Called by __getitem__ for missing key; pseudo-code:\n\ | 
 |   if self.default_factory is None: raise KeyError((key,))\n\ | 
 |   self[key] = value = self.default_factory()\n\ | 
 |   return value\n\ | 
 | "); | 
 |  | 
 | static PyObject * | 
 | defdict_missing(defdictobject *dd, PyObject *key) | 
 | { | 
 |     PyObject *factory = dd->default_factory; | 
 |     PyObject *value; | 
 |     if (factory == NULL || factory == Py_None) { | 
 |         /* XXX Call dict.__missing__(key) */ | 
 |         PyObject *tup; | 
 |         tup = PyTuple_Pack(1, key); | 
 |         if (!tup) return NULL; | 
 |         PyErr_SetObject(PyExc_KeyError, tup); | 
 |         Py_DECREF(tup); | 
 |         return NULL; | 
 |     } | 
 |     value = _PyObject_CallNoArg(factory); | 
 |     if (value == NULL) | 
 |         return value; | 
 |     if (PyObject_SetItem((PyObject *)dd, key, value) < 0) { | 
 |         Py_DECREF(value); | 
 |         return NULL; | 
 |     } | 
 |     return value; | 
 | } | 
 |  | 
 | PyDoc_STRVAR(defdict_copy_doc, "D.copy() -> a shallow copy of D."); | 
 |  | 
 | static PyObject * | 
 | defdict_copy(defdictobject *dd, PyObject *Py_UNUSED(ignored)) | 
 | { | 
 |     /* This calls the object's class.  That only works for subclasses | 
 |        whose class constructor has the same signature.  Subclasses that | 
 |        define a different constructor signature must override copy(). | 
 |     */ | 
 |  | 
 |     if (dd->default_factory == NULL) | 
 |         return PyObject_CallFunctionObjArgs((PyObject*)Py_TYPE(dd), Py_None, dd, NULL); | 
 |     return PyObject_CallFunctionObjArgs((PyObject*)Py_TYPE(dd), | 
 |                                         dd->default_factory, dd, NULL); | 
 | } | 
 |  | 
 | static PyObject * | 
 | defdict_reduce(defdictobject *dd, PyObject *Py_UNUSED(ignored)) | 
 | { | 
 |     /* __reduce__ must return a 5-tuple as follows: | 
 |  | 
 |        - factory function | 
 |        - tuple of args for the factory function | 
 |        - additional state (here None) | 
 |        - sequence iterator (here None) | 
 |        - dictionary iterator (yielding successive (key, value) pairs | 
 |  | 
 |        This API is used by pickle.py and copy.py. | 
 |  | 
 |        For this to be useful with pickle.py, the default_factory | 
 |        must be picklable; e.g., None, a built-in, or a global | 
 |        function in a module or package. | 
 |  | 
 |        Both shallow and deep copying are supported, but for deep | 
 |        copying, the default_factory must be deep-copyable; e.g. None, | 
 |        or a built-in (functions are not copyable at this time). | 
 |  | 
 |        This only works for subclasses as long as their constructor | 
 |        signature is compatible; the first argument must be the | 
 |        optional default_factory, defaulting to None. | 
 |     */ | 
 |     PyObject *args; | 
 |     PyObject *items; | 
 |     PyObject *iter; | 
 |     PyObject *result; | 
 |     _Py_IDENTIFIER(items); | 
 |  | 
 |     if (dd->default_factory == NULL || dd->default_factory == Py_None) | 
 |         args = PyTuple_New(0); | 
 |     else | 
 |         args = PyTuple_Pack(1, dd->default_factory); | 
 |     if (args == NULL) | 
 |         return NULL; | 
 |     items = _PyObject_CallMethodIdNoArgs((PyObject *)dd, &PyId_items); | 
 |     if (items == NULL) { | 
 |         Py_DECREF(args); | 
 |         return NULL; | 
 |     } | 
 |     iter = PyObject_GetIter(items); | 
 |     if (iter == NULL) { | 
 |         Py_DECREF(items); | 
 |         Py_DECREF(args); | 
 |         return NULL; | 
 |     } | 
 |     result = PyTuple_Pack(5, Py_TYPE(dd), args, | 
 |                           Py_None, Py_None, iter); | 
 |     Py_DECREF(iter); | 
 |     Py_DECREF(items); | 
 |     Py_DECREF(args); | 
 |     return result; | 
 | } | 
 |  | 
 | static PyMethodDef defdict_methods[] = { | 
 |     {"__missing__", (PyCFunction)defdict_missing, METH_O, | 
 |      defdict_missing_doc}, | 
 |     {"copy", (PyCFunction)defdict_copy, METH_NOARGS, | 
 |      defdict_copy_doc}, | 
 |     {"__copy__", (PyCFunction)defdict_copy, METH_NOARGS, | 
 |      defdict_copy_doc}, | 
 |     {"__reduce__", (PyCFunction)defdict_reduce, METH_NOARGS, | 
 |      reduce_doc}, | 
 |     {NULL} | 
 | }; | 
 |  | 
 | static PyMemberDef defdict_members[] = { | 
 |     {"default_factory", T_OBJECT, | 
 |      offsetof(defdictobject, default_factory), 0, | 
 |      PyDoc_STR("Factory for default value called by __missing__().")}, | 
 |     {NULL} | 
 | }; | 
 |  | 
 | static void | 
 | defdict_dealloc(defdictobject *dd) | 
 | { | 
 |     /* bpo-31095: UnTrack is needed before calling any callbacks */ | 
 |     PyObject_GC_UnTrack(dd); | 
 |     Py_CLEAR(dd->default_factory); | 
 |     PyDict_Type.tp_dealloc((PyObject *)dd); | 
 | } | 
 |  | 
 | static PyObject * | 
 | defdict_repr(defdictobject *dd) | 
 | { | 
 |     PyObject *baserepr; | 
 |     PyObject *defrepr; | 
 |     PyObject *result; | 
 |     baserepr = PyDict_Type.tp_repr((PyObject *)dd); | 
 |     if (baserepr == NULL) | 
 |         return NULL; | 
 |     if (dd->default_factory == NULL) | 
 |         defrepr = PyUnicode_FromString("None"); | 
 |     else | 
 |     { | 
 |         int status = Py_ReprEnter(dd->default_factory); | 
 |         if (status != 0) { | 
 |             if (status < 0) { | 
 |                 Py_DECREF(baserepr); | 
 |                 return NULL; | 
 |             } | 
 |             defrepr = PyUnicode_FromString("..."); | 
 |         } | 
 |         else | 
 |             defrepr = PyObject_Repr(dd->default_factory); | 
 |         Py_ReprLeave(dd->default_factory); | 
 |     } | 
 |     if (defrepr == NULL) { | 
 |         Py_DECREF(baserepr); | 
 |         return NULL; | 
 |     } | 
 |     result = PyUnicode_FromFormat("%s(%U, %U)", | 
 |                                   _PyType_Name(Py_TYPE(dd)), | 
 |                                   defrepr, baserepr); | 
 |     Py_DECREF(defrepr); | 
 |     Py_DECREF(baserepr); | 
 |     return result; | 
 | } | 
 |  | 
 | static int | 
 | defdict_traverse(PyObject *self, visitproc visit, void *arg) | 
 | { | 
 |     Py_VISIT(((defdictobject *)self)->default_factory); | 
 |     return PyDict_Type.tp_traverse(self, visit, arg); | 
 | } | 
 |  | 
 | static int | 
 | defdict_tp_clear(defdictobject *dd) | 
 | { | 
 |     Py_CLEAR(dd->default_factory); | 
 |     return PyDict_Type.tp_clear((PyObject *)dd); | 
 | } | 
 |  | 
 | static int | 
 | defdict_init(PyObject *self, PyObject *args, PyObject *kwds) | 
 | { | 
 |     defdictobject *dd = (defdictobject *)self; | 
 |     PyObject *olddefault = dd->default_factory; | 
 |     PyObject *newdefault = NULL; | 
 |     PyObject *newargs; | 
 |     int result; | 
 |     if (args == NULL || !PyTuple_Check(args)) | 
 |         newargs = PyTuple_New(0); | 
 |     else { | 
 |         Py_ssize_t n = PyTuple_GET_SIZE(args); | 
 |         if (n > 0) { | 
 |             newdefault = PyTuple_GET_ITEM(args, 0); | 
 |             if (!PyCallable_Check(newdefault) && newdefault != Py_None) { | 
 |                 PyErr_SetString(PyExc_TypeError, | 
 |                     "first argument must be callable or None"); | 
 |                 return -1; | 
 |             } | 
 |         } | 
 |         newargs = PySequence_GetSlice(args, 1, n); | 
 |     } | 
 |     if (newargs == NULL) | 
 |         return -1; | 
 |     Py_XINCREF(newdefault); | 
 |     dd->default_factory = newdefault; | 
 |     result = PyDict_Type.tp_init(self, newargs, kwds); | 
 |     Py_DECREF(newargs); | 
 |     Py_XDECREF(olddefault); | 
 |     return result; | 
 | } | 
 |  | 
 | PyDoc_STRVAR(defdict_doc, | 
 | "defaultdict(default_factory[, ...]) --> dict with default factory\n\ | 
 | \n\ | 
 | The default factory is called without arguments to produce\n\ | 
 | a new value when a key is not present, in __getitem__ only.\n\ | 
 | A defaultdict compares equal to a dict with the same items.\n\ | 
 | All remaining arguments are treated the same as if they were\n\ | 
 | passed to the dict constructor, including keyword arguments.\n\ | 
 | "); | 
 |  | 
 | /* See comment in xxsubtype.c */ | 
 | #define DEFERRED_ADDRESS(ADDR) 0 | 
 |  | 
 | static PyTypeObject defdict_type = { | 
 |     PyVarObject_HEAD_INIT(DEFERRED_ADDRESS(&PyType_Type), 0) | 
 |     "collections.defaultdict",          /* tp_name */ | 
 |     sizeof(defdictobject),              /* tp_basicsize */ | 
 |     0,                                  /* tp_itemsize */ | 
 |     /* methods */ | 
 |     (destructor)defdict_dealloc,        /* tp_dealloc */ | 
 |     0,                                  /* tp_vectorcall_offset */ | 
 |     0,                                  /* tp_getattr */ | 
 |     0,                                  /* tp_setattr */ | 
 |     0,                                  /* tp_as_async */ | 
 |     (reprfunc)defdict_repr,             /* tp_repr */ | 
 |     0,                                  /* tp_as_number */ | 
 |     0,                                  /* tp_as_sequence */ | 
 |     0,                                  /* tp_as_mapping */ | 
 |     0,                                  /* tp_hash */ | 
 |     0,                                  /* tp_call */ | 
 |     0,                                  /* tp_str */ | 
 |     PyObject_GenericGetAttr,            /* tp_getattro */ | 
 |     0,                                  /* tp_setattro */ | 
 |     0,                                  /* tp_as_buffer */ | 
 |     Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_GC, | 
 |                                     /* tp_flags */ | 
 |     defdict_doc,                        /* tp_doc */ | 
 |     defdict_traverse,                   /* tp_traverse */ | 
 |     (inquiry)defdict_tp_clear,          /* tp_clear */ | 
 |     0,                                  /* tp_richcompare */ | 
 |     0,                                  /* tp_weaklistoffset*/ | 
 |     0,                                  /* tp_iter */ | 
 |     0,                                  /* tp_iternext */ | 
 |     defdict_methods,                    /* tp_methods */ | 
 |     defdict_members,                    /* tp_members */ | 
 |     0,                                  /* tp_getset */ | 
 |     DEFERRED_ADDRESS(&PyDict_Type),     /* tp_base */ | 
 |     0,                                  /* tp_dict */ | 
 |     0,                                  /* tp_descr_get */ | 
 |     0,                                  /* tp_descr_set */ | 
 |     0,                                  /* tp_dictoffset */ | 
 |     defdict_init,                       /* tp_init */ | 
 |     PyType_GenericAlloc,                /* tp_alloc */ | 
 |     0,                                  /* tp_new */ | 
 |     PyObject_GC_Del,                    /* tp_free */ | 
 | }; | 
 |  | 
 | /* helper function for Counter  *********************************************/ | 
 |  | 
 | /*[clinic input] | 
 | _collections._count_elements | 
 |  | 
 |     mapping: object | 
 |     iterable: object | 
 |     / | 
 |  | 
 | Count elements in the iterable, updating the mapping | 
 | [clinic start generated code]*/ | 
 |  | 
 | static PyObject * | 
 | _collections__count_elements_impl(PyObject *module, PyObject *mapping, | 
 |                                   PyObject *iterable) | 
 | /*[clinic end generated code: output=7e0c1789636b3d8f input=e79fad04534a0b45]*/ | 
 | { | 
 |     _Py_IDENTIFIER(get); | 
 |     _Py_IDENTIFIER(__setitem__); | 
 |     PyObject *it, *oldval; | 
 |     PyObject *newval = NULL; | 
 |     PyObject *key = NULL; | 
 |     PyObject *bound_get = NULL; | 
 |     PyObject *mapping_get; | 
 |     PyObject *dict_get; | 
 |     PyObject *mapping_setitem; | 
 |     PyObject *dict_setitem; | 
 |  | 
 |     it = PyObject_GetIter(iterable); | 
 |     if (it == NULL) | 
 |         return NULL; | 
 |  | 
 |     /* Only take the fast path when get() and __setitem__() | 
 |      * have not been overridden. | 
 |      */ | 
 |     mapping_get = _PyType_LookupId(Py_TYPE(mapping), &PyId_get); | 
 |     dict_get = _PyType_LookupId(&PyDict_Type, &PyId_get); | 
 |     mapping_setitem = _PyType_LookupId(Py_TYPE(mapping), &PyId___setitem__); | 
 |     dict_setitem = _PyType_LookupId(&PyDict_Type, &PyId___setitem__); | 
 |  | 
 |     if (mapping_get != NULL && mapping_get == dict_get && | 
 |         mapping_setitem != NULL && mapping_setitem == dict_setitem && | 
 |         PyDict_Check(mapping)) | 
 |     { | 
 |         while (1) { | 
 |             /* Fast path advantages: | 
 |                    1. Eliminate double hashing | 
 |                       (by re-using the same hash for both the get and set) | 
 |                    2. Avoid argument overhead of PyObject_CallFunctionObjArgs | 
 |                       (argument tuple creation and parsing) | 
 |                    3. Avoid indirection through a bound method object | 
 |                       (creates another argument tuple) | 
 |                    4. Avoid initial increment from zero | 
 |                       (reuse an existing one-object instead) | 
 |             */ | 
 |             Py_hash_t hash; | 
 |  | 
 |             key = PyIter_Next(it); | 
 |             if (key == NULL) | 
 |                 break; | 
 |  | 
 |             if (!PyUnicode_CheckExact(key) || | 
 |                 (hash = ((PyASCIIObject *) key)->hash) == -1) | 
 |             { | 
 |                 hash = PyObject_Hash(key); | 
 |                 if (hash == -1) | 
 |                     goto done; | 
 |             } | 
 |  | 
 |             oldval = _PyDict_GetItem_KnownHash(mapping, key, hash); | 
 |             if (oldval == NULL) { | 
 |                 if (PyErr_Occurred()) | 
 |                     goto done; | 
 |                 if (_PyDict_SetItem_KnownHash(mapping, key, _PyLong_One, hash) < 0) | 
 |                     goto done; | 
 |             } else { | 
 |                 newval = PyNumber_Add(oldval, _PyLong_One); | 
 |                 if (newval == NULL) | 
 |                     goto done; | 
 |                 if (_PyDict_SetItem_KnownHash(mapping, key, newval, hash) < 0) | 
 |                     goto done; | 
 |                 Py_CLEAR(newval); | 
 |             } | 
 |             Py_DECREF(key); | 
 |         } | 
 |     } else { | 
 |         bound_get = _PyObject_GetAttrId(mapping, &PyId_get); | 
 |         if (bound_get == NULL) | 
 |             goto done; | 
 |  | 
 |         while (1) { | 
 |             key = PyIter_Next(it); | 
 |             if (key == NULL) | 
 |                 break; | 
 |             oldval = PyObject_CallFunctionObjArgs(bound_get, key, _PyLong_Zero, NULL); | 
 |             if (oldval == NULL) | 
 |                 break; | 
 |             newval = PyNumber_Add(oldval, _PyLong_One); | 
 |             Py_DECREF(oldval); | 
 |             if (newval == NULL) | 
 |                 break; | 
 |             if (PyObject_SetItem(mapping, key, newval) < 0) | 
 |                 break; | 
 |             Py_CLEAR(newval); | 
 |             Py_DECREF(key); | 
 |         } | 
 |     } | 
 |  | 
 | done: | 
 |     Py_DECREF(it); | 
 |     Py_XDECREF(key); | 
 |     Py_XDECREF(newval); | 
 |     Py_XDECREF(bound_get); | 
 |     if (PyErr_Occurred()) | 
 |         return NULL; | 
 |     Py_RETURN_NONE; | 
 | } | 
 |  | 
 | /* Helper function for namedtuple() ************************************/ | 
 |  | 
 | typedef struct { | 
 |     PyObject_HEAD | 
 |     Py_ssize_t index; | 
 |     PyObject* doc; | 
 | } _tuplegetterobject; | 
 |  | 
 | /*[clinic input] | 
 | @classmethod | 
 | _tuplegetter.__new__ as tuplegetter_new | 
 |  | 
 |     index: Py_ssize_t | 
 |     doc: object | 
 |     / | 
 | [clinic start generated code]*/ | 
 |  | 
 | static PyObject * | 
 | tuplegetter_new_impl(PyTypeObject *type, Py_ssize_t index, PyObject *doc) | 
 | /*[clinic end generated code: output=014be444ad80263f input=87c576a5bdbc0bbb]*/ | 
 | { | 
 |     _tuplegetterobject* self; | 
 |     self = (_tuplegetterobject *)type->tp_alloc(type, 0); | 
 |     if (self == NULL) { | 
 |         return NULL; | 
 |     } | 
 |     self->index = index; | 
 |     Py_INCREF(doc); | 
 |     self->doc = doc; | 
 |     return (PyObject *)self; | 
 | } | 
 |  | 
 | static PyObject * | 
 | tuplegetter_descr_get(PyObject *self, PyObject *obj, PyObject *type) | 
 | { | 
 |     Py_ssize_t index = ((_tuplegetterobject*)self)->index; | 
 |     PyObject *result; | 
 |  | 
 |     if (obj == NULL) { | 
 |         Py_INCREF(self); | 
 |         return self; | 
 |     } | 
 |     if (!PyTuple_Check(obj)) { | 
 |         if (obj == Py_None) { | 
 |             Py_INCREF(self); | 
 |             return self; | 
 |         } | 
 |         PyErr_Format(PyExc_TypeError, | 
 |                      "descriptor for index '%zd' for tuple subclasses " | 
 |                      "doesn't apply to '%s' object", | 
 |                      index, | 
 |                      obj->ob_type->tp_name); | 
 |         return NULL; | 
 |     } | 
 |  | 
 |     if (!valid_index(index, PyTuple_GET_SIZE(obj))) { | 
 |         PyErr_SetString(PyExc_IndexError, "tuple index out of range"); | 
 |         return NULL; | 
 |     } | 
 |  | 
 |     result = PyTuple_GET_ITEM(obj, index); | 
 |     Py_INCREF(result); | 
 |     return result; | 
 | } | 
 |  | 
 | static int | 
 | tuplegetter_descr_set(PyObject *self, PyObject *obj, PyObject *value) | 
 | { | 
 |     if (value == NULL) { | 
 |         PyErr_SetString(PyExc_AttributeError, "can't delete attribute"); | 
 |     } else { | 
 |         PyErr_SetString(PyExc_AttributeError, "can't set attribute"); | 
 |     } | 
 |     return -1; | 
 | } | 
 |  | 
 | static int | 
 | tuplegetter_traverse(PyObject *self, visitproc visit, void *arg) | 
 | { | 
 |     _tuplegetterobject *tuplegetter = (_tuplegetterobject *)self; | 
 |     Py_VISIT(tuplegetter->doc); | 
 |     return 0; | 
 | } | 
 |  | 
 | static int | 
 | tuplegetter_clear(PyObject *self) | 
 | { | 
 |     _tuplegetterobject *tuplegetter = (_tuplegetterobject *)self; | 
 |     Py_CLEAR(tuplegetter->doc); | 
 |     return 0; | 
 | } | 
 |  | 
 | static void | 
 | tuplegetter_dealloc(_tuplegetterobject *self) | 
 | { | 
 |     PyObject_GC_UnTrack(self); | 
 |     tuplegetter_clear((PyObject*)self); | 
 |     Py_TYPE(self)->tp_free((PyObject*)self); | 
 | } | 
 |  | 
 | static PyObject* | 
 | tuplegetter_reduce(_tuplegetterobject *self, PyObject *Py_UNUSED(ignored)) | 
 | { | 
 |     return Py_BuildValue("(O(nO))", (PyObject*) Py_TYPE(self), self->index, self->doc); | 
 | } | 
 |  | 
 |  | 
 | static PyMemberDef tuplegetter_members[] = { | 
 |     {"__doc__",  T_OBJECT, offsetof(_tuplegetterobject, doc), 0}, | 
 |     {0} | 
 | }; | 
 |  | 
 | static PyMethodDef tuplegetter_methods[] = { | 
 |     {"__reduce__", (PyCFunction)tuplegetter_reduce, METH_NOARGS, NULL}, | 
 |     {NULL}, | 
 | }; | 
 |  | 
 | static PyTypeObject tuplegetter_type = { | 
 |     PyVarObject_HEAD_INIT(NULL, 0) | 
 |     "_collections._tuplegetter",                /* tp_name */ | 
 |     sizeof(_tuplegetterobject),                 /* tp_basicsize */ | 
 |     0,                                          /* tp_itemsize */ | 
 |     /* methods */ | 
 |     (destructor)tuplegetter_dealloc,            /* tp_dealloc */ | 
 |     0,                                          /* tp_vectorcall_offset */ | 
 |     0,                                          /* tp_getattr */ | 
 |     0,                                          /* tp_setattr */ | 
 |     0,                                          /* tp_as_async */ | 
 |     0,                                          /* tp_repr */ | 
 |     0,                                          /* tp_as_number */ | 
 |     0,                                          /* tp_as_sequence */ | 
 |     0,                                          /* tp_as_mapping */ | 
 |     0,                                          /* tp_hash */ | 
 |     0,                                          /* tp_call */ | 
 |     0,                                          /* tp_str */ | 
 |     0,                                          /* tp_getattro */ | 
 |     0,                                          /* tp_setattro */ | 
 |     0,                                          /* tp_as_buffer */ | 
 |     Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,    /* tp_flags */ | 
 |     0,                                          /* tp_doc */ | 
 |     (traverseproc)tuplegetter_traverse,         /* tp_traverse */ | 
 |     (inquiry)tuplegetter_clear,                 /* tp_clear */ | 
 |     0,                                          /* tp_richcompare */ | 
 |     0,                                          /* tp_weaklistoffset */ | 
 |     0,                                          /* tp_iter */ | 
 |     0,                                          /* tp_iternext */ | 
 |     tuplegetter_methods,                        /* tp_methods */ | 
 |     tuplegetter_members,                        /* tp_members */ | 
 |     0,                                          /* tp_getset */ | 
 |     0,                                          /* tp_base */ | 
 |     0,                                          /* tp_dict */ | 
 |     tuplegetter_descr_get,                      /* tp_descr_get */ | 
 |     tuplegetter_descr_set,                      /* tp_descr_set */ | 
 |     0,                                          /* tp_dictoffset */ | 
 |     0,                                          /* tp_init */ | 
 |     0,                                          /* tp_alloc */ | 
 |     tuplegetter_new,                            /* tp_new */ | 
 |     0, | 
 | }; | 
 |  | 
 |  | 
 | /* module level code ********************************************************/ | 
 |  | 
 | PyDoc_STRVAR(module_doc, | 
 | "High performance data structures.\n\ | 
 | - deque:        ordered collection accessible from endpoints only\n\ | 
 | - defaultdict:  dict subclass with a default value factory\n\ | 
 | "); | 
 |  | 
 | static struct PyMethodDef module_functions[] = { | 
 |     _COLLECTIONS__COUNT_ELEMENTS_METHODDEF | 
 |     {NULL,       NULL}          /* sentinel */ | 
 | }; | 
 |  | 
 | static struct PyModuleDef _collectionsmodule = { | 
 |     PyModuleDef_HEAD_INIT, | 
 |     "_collections", | 
 |     module_doc, | 
 |     -1, | 
 |     module_functions, | 
 |     NULL, | 
 |     NULL, | 
 |     NULL, | 
 |     NULL | 
 | }; | 
 |  | 
 | PyMODINIT_FUNC | 
 | PyInit__collections(void) | 
 | { | 
 |     PyObject *m; | 
 |  | 
 |     m = PyModule_Create(&_collectionsmodule); | 
 |     if (m == NULL) | 
 |         return NULL; | 
 |  | 
 |     if (PyType_Ready(&deque_type) < 0) | 
 |         return NULL; | 
 |     Py_INCREF(&deque_type); | 
 |     PyModule_AddObject(m, "deque", (PyObject *)&deque_type); | 
 |  | 
 |     defdict_type.tp_base = &PyDict_Type; | 
 |     if (PyType_Ready(&defdict_type) < 0) | 
 |         return NULL; | 
 |     Py_INCREF(&defdict_type); | 
 |     PyModule_AddObject(m, "defaultdict", (PyObject *)&defdict_type); | 
 |  | 
 |     Py_INCREF(&PyODict_Type); | 
 |     PyModule_AddObject(m, "OrderedDict", (PyObject *)&PyODict_Type); | 
 |  | 
 |     if (PyType_Ready(&dequeiter_type) < 0) | 
 |         return NULL; | 
 |     Py_INCREF(&dequeiter_type); | 
 |     PyModule_AddObject(m, "_deque_iterator", (PyObject *)&dequeiter_type); | 
 |  | 
 |     if (PyType_Ready(&dequereviter_type) < 0) | 
 |         return NULL; | 
 |     Py_INCREF(&dequereviter_type); | 
 |     PyModule_AddObject(m, "_deque_reverse_iterator", (PyObject *)&dequereviter_type); | 
 |  | 
 |     if (PyType_Ready(&tuplegetter_type) < 0) | 
 |         return NULL; | 
 |     Py_INCREF(&tuplegetter_type); | 
 |     PyModule_AddObject(m, "_tuplegetter", (PyObject *)&tuplegetter_type); | 
 |  | 
 |     return m; | 
 | } |