diff options
| -rw-r--r-- | Modules/collectionsmodule.c | 103 |
1 files changed, 102 insertions, 1 deletions
diff --git a/Modules/collectionsmodule.c b/Modules/collectionsmodule.c index ddc6f88..cf474f7 100644 --- a/Modules/collectionsmodule.c +++ b/Modules/collectionsmodule.c @@ -645,6 +645,9 @@ static PySequenceMethods deque_as_sequence = { /* deque object ********************************************************/ static PyObject *deque_iter(dequeobject *deque); +static PyObject *deque_reviter(dequeobject *deque); +PyDoc_STRVAR(reversed_doc, + "D.__reversed__() -- return a reverse iterator over the deque"); static PyMethodDef deque_methods[] = { {"append", (PyCFunction)deque_append, @@ -665,6 +668,8 @@ static PyMethodDef deque_methods[] = { METH_NOARGS, popleft_doc}, {"__reduce__", (PyCFunction)deque_reduce, METH_NOARGS, reduce_doc}, + {"__reversed__", (PyCFunction)deque_reviter, + METH_NOARGS, reversed_doc}, {"rotate", (PyCFunction)deque_rotate, METH_VARARGS, rotate_doc}, {NULL, NULL} /* sentinel */ @@ -727,6 +732,7 @@ typedef struct { block *b; dequeobject *deque; int len; + int counter; } dequeiterobject; PyTypeObject dequeiter_type; @@ -744,6 +750,7 @@ deque_iter(dequeobject *deque) Py_INCREF(deque); it->deque = deque; it->len = deque->len; + it->counter = deque->len; return (PyObject *)it; } @@ -774,10 +781,22 @@ dequeiter_next(dequeiterobject *it) it->b = it->b->rightlink; it->index = 0; } + it->counter--; Py_INCREF(item); return item; } +static int +dequeiter_len(dequeiterobject *it) +{ + return it->counter; +} + +static PySequenceMethods dequeiter_as_sequence = { + (inquiry)dequeiter_len, /* sq_length */ + 0, /* sq_concat */ +}; + PyTypeObject dequeiter_type = { PyObject_HEAD_INIT(NULL) 0, /* ob_size */ @@ -792,7 +811,7 @@ PyTypeObject dequeiter_type = { 0, /* tp_compare */ 0, /* tp_repr */ 0, /* tp_as_number */ - 0, /* tp_as_sequence */ + &dequeiter_as_sequence, /* tp_as_sequence */ 0, /* tp_as_mapping */ 0, /* tp_hash */ 0, /* tp_call */ @@ -811,6 +830,85 @@ PyTypeObject dequeiter_type = { 0, }; +/*********************** Deque Reverse Iterator **************************/ + +PyTypeObject dequereviter_type; + +static PyObject * +deque_reviter(dequeobject *deque) +{ + dequeiterobject *it; + + it = PyObject_New(dequeiterobject, &dequereviter_type); + if (it == NULL) + return NULL; + it->b = deque->rightblock; + it->index = deque->rightindex; + Py_INCREF(deque); + it->deque = deque; + it->len = deque->len; + it->counter = deque->len; + return (PyObject *)it; +} + +static PyObject * +dequereviter_next(dequeiterobject *it) +{ + PyObject *item; + if (it->b == it->deque->leftblock && it->index < it->deque->leftindex) + return NULL; + + if (it->len != it->deque->len) { + it->len = -1; /* Make this state sticky */ + PyErr_SetString(PyExc_RuntimeError, + "deque changed size during iteration"); + return NULL; + } + + item = it->b->data[it->index]; + it->index--; + if (it->index == -1 && it->b->leftlink != NULL) { + it->b = it->b->leftlink; + it->index = BLOCKLEN - 1; + } + it->counter--; + Py_INCREF(item); + return item; +} + +PyTypeObject dequereviter_type = { + PyObject_HEAD_INIT(NULL) + 0, /* ob_size */ + "deque_reverse_iterator", /* tp_name */ + sizeof(dequeiterobject), /* tp_basicsize */ + 0, /* tp_itemsize */ + /* methods */ + (destructor)dequeiter_dealloc, /* tp_dealloc */ + 0, /* tp_print */ + 0, /* tp_getattr */ + 0, /* tp_setattr */ + 0, /* tp_compare */ + 0, /* tp_repr */ + 0, /* tp_as_number */ + &dequeiter_as_sequence, /* 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, /* tp_flags */ + 0, /* tp_doc */ + 0, /* tp_traverse */ + 0, /* tp_clear */ + 0, /* tp_richcompare */ + 0, /* tp_weaklistoffset */ + PyObject_SelfIter, /* tp_iter */ + (iternextfunc)dequereviter_next, /* tp_iternext */ + 0, +}; + /* module level code ********************************************************/ PyDoc_STRVAR(module_doc, @@ -832,5 +930,8 @@ initcollections(void) if (PyType_Ready(&dequeiter_type) < 0) return; + if (PyType_Ready(&dequereviter_type) < 0) + return; + return; } |