Staging
v0.5.1
v0.5.1
https://github.com/python/cpython
Tip revision: 1da43e5e916949c8e849e656d9d05fa4b9d6836c authored by Benjamin Peterson on 26 June 2009, 13:21:52 UTC
rearrange the sections of the README, so they'll hopefully be more in the order people will interested in
rearrange the sections of the README, so they'll hopefully be more in the order people will interested in
Tip revision: 1da43e5
_functoolsmodule.c
#include "Python.h"
#include "structmember.h"
/* _functools module written and maintained
by Hye-Shik Chang <perky@FreeBSD.org>
with adaptations by Raymond Hettinger <python@rcn.com>
Copyright (c) 2004, 2005, 2006 Python Software Foundation.
All rights reserved.
*/
/* partial object **********************************************************/
typedef struct {
PyObject_HEAD
PyObject *fn;
PyObject *args;
PyObject *kw;
PyObject *dict;
PyObject *weakreflist; /* List of weak references */
} partialobject;
static PyTypeObject partial_type;
static PyObject *
partial_new(PyTypeObject *type, PyObject *args, PyObject *kw)
{
PyObject *func;
partialobject *pto;
if (PyTuple_GET_SIZE(args) < 1) {
PyErr_SetString(PyExc_TypeError,
"type 'partial' takes at least one argument");
return NULL;
}
func = PyTuple_GET_ITEM(args, 0);
if (!PyCallable_Check(func)) {
PyErr_SetString(PyExc_TypeError,
"the first argument must be callable");
return NULL;
}
/* create partialobject structure */
pto = (partialobject *)type->tp_alloc(type, 0);
if (pto == NULL)
return NULL;
pto->fn = func;
Py_INCREF(func);
pto->args = PyTuple_GetSlice(args, 1, PY_SSIZE_T_MAX);
if (pto->args == NULL) {
pto->kw = NULL;
Py_DECREF(pto);
return NULL;
}
if (kw != NULL) {
pto->kw = PyDict_Copy(kw);
if (pto->kw == NULL) {
Py_DECREF(pto);
return NULL;
}
} else {
pto->kw = Py_None;
Py_INCREF(Py_None);
}
pto->weakreflist = NULL;
pto->dict = NULL;
return (PyObject *)pto;
}
static void
partial_dealloc(partialobject *pto)
{
PyObject_GC_UnTrack(pto);
if (pto->weakreflist != NULL)
PyObject_ClearWeakRefs((PyObject *) pto);
Py_XDECREF(pto->fn);
Py_XDECREF(pto->args);
Py_XDECREF(pto->kw);
Py_XDECREF(pto->dict);
Py_TYPE(pto)->tp_free(pto);
}
static PyObject *
partial_call(partialobject *pto, PyObject *args, PyObject *kw)
{
PyObject *ret;
PyObject *argappl = NULL, *kwappl = NULL;
assert (PyCallable_Check(pto->fn));
assert (PyTuple_Check(pto->args));
assert (pto->kw == Py_None || PyDict_Check(pto->kw));
if (PyTuple_GET_SIZE(pto->args) == 0) {
argappl = args;
Py_INCREF(args);
} else if (PyTuple_GET_SIZE(args) == 0) {
argappl = pto->args;
Py_INCREF(pto->args);
} else {
argappl = PySequence_Concat(pto->args, args);
if (argappl == NULL)
return NULL;
}
if (pto->kw == Py_None) {
kwappl = kw;
Py_XINCREF(kw);
} else {
kwappl = PyDict_Copy(pto->kw);
if (kwappl == NULL) {
Py_DECREF(argappl);
return NULL;
}
if (kw != NULL) {
if (PyDict_Merge(kwappl, kw, 1) != 0) {
Py_DECREF(argappl);
Py_DECREF(kwappl);
return NULL;
}
}
}
ret = PyObject_Call(pto->fn, argappl, kwappl);
Py_DECREF(argappl);
Py_XDECREF(kwappl);
return ret;
}
static int
partial_traverse(partialobject *pto, visitproc visit, void *arg)
{
Py_VISIT(pto->fn);
Py_VISIT(pto->args);
Py_VISIT(pto->kw);
Py_VISIT(pto->dict);
return 0;
}
PyDoc_STRVAR(partial_doc,
"partial(func, *args, **keywords) - new function with partial application\n\
of the given arguments and keywords.\n");
#define OFF(x) offsetof(partialobject, x)
static PyMemberDef partial_memberlist[] = {
{"func", T_OBJECT, OFF(fn), READONLY,
"function object to use in future partial calls"},
{"args", T_OBJECT, OFF(args), READONLY,
"tuple of arguments to future partial calls"},
{"keywords", T_OBJECT, OFF(kw), READONLY,
"dictionary of keyword arguments to future partial calls"},
{NULL} /* Sentinel */
};
static PyObject *
partial_get_dict(partialobject *pto)
{
if (pto->dict == NULL) {
pto->dict = PyDict_New();
if (pto->dict == NULL)
return NULL;
}
Py_INCREF(pto->dict);
return pto->dict;
}
static int
partial_set_dict(partialobject *pto, PyObject *value)
{
PyObject *tmp;
/* It is illegal to del p.__dict__ */
if (value == NULL) {
PyErr_SetString(PyExc_TypeError,
"a partial object's dictionary may not be deleted");
return -1;
}
/* Can only set __dict__ to a dictionary */
if (!PyDict_Check(value)) {
PyErr_SetString(PyExc_TypeError,
"setting partial object's dictionary to a non-dict");
return -1;
}
tmp = pto->dict;
Py_INCREF(value);
pto->dict = value;
Py_XDECREF(tmp);
return 0;
}
static PyGetSetDef partial_getsetlist[] = {
{"__dict__", (getter)partial_get_dict, (setter)partial_set_dict},
{NULL} /* Sentinel */
};
/* Pickle strategy:
__reduce__ by itself doesn't support getting kwargs in the unpickle
operation so we define a __setstate__ that replaces all the information
about the partial. If we only replaced part of it someone would use
it as a hook to do stange things.
*/
static PyObject *
partial_reduce(partialobject *pto, PyObject *unused)
{
return Py_BuildValue("O(O)(OOOO)", Py_TYPE(pto), pto->fn, pto->fn,
pto->args, pto->kw,
pto->dict ? pto->dict : Py_None);
}
static PyObject *
partial_setstate(partialobject *pto, PyObject *args)
{
PyObject *fn, *fnargs, *kw, *dict;
if (!PyArg_ParseTuple(args, "(OOOO):__setstate__",
&fn, &fnargs, &kw, &dict))
return NULL;
Py_XDECREF(pto->fn);
Py_XDECREF(pto->args);
Py_XDECREF(pto->kw);
Py_XDECREF(pto->dict);
pto->fn = fn;
pto->args = fnargs;
pto->kw = kw;
if (dict != Py_None) {
pto->dict = dict;
Py_INCREF(dict);
} else {
pto->dict = NULL;
}
Py_INCREF(fn);
Py_INCREF(fnargs);
Py_INCREF(kw);
Py_RETURN_NONE;
}
static PyMethodDef partial_methods[] = {
{"__reduce__", (PyCFunction)partial_reduce, METH_NOARGS},
{"__setstate__", (PyCFunction)partial_setstate, METH_VARARGS},
{NULL, NULL} /* sentinel */
};
static PyTypeObject partial_type = {
PyVarObject_HEAD_INIT(NULL, 0)
"functools.partial", /* tp_name */
sizeof(partialobject), /* tp_basicsize */
0, /* tp_itemsize */
/* methods */
(destructor)partial_dealloc, /* tp_dealloc */
0, /* tp_print */
0, /* tp_getattr */
0, /* tp_setattr */
0, /* tp_reserved */
0, /* tp_repr */
0, /* tp_as_number */
0, /* tp_as_sequence */
0, /* tp_as_mapping */
0, /* tp_hash */
(ternaryfunc)partial_call, /* tp_call */
0, /* tp_str */
PyObject_GenericGetAttr, /* tp_getattro */
PyObject_GenericSetAttr, /* tp_setattro */
0, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC |
Py_TPFLAGS_BASETYPE, /* tp_flags */
partial_doc, /* tp_doc */
(traverseproc)partial_traverse, /* tp_traverse */
0, /* tp_clear */
0, /* tp_richcompare */
offsetof(partialobject, weakreflist), /* tp_weaklistoffset */
0, /* tp_iter */
0, /* tp_iternext */
partial_methods, /* tp_methods */
partial_memberlist, /* tp_members */
partial_getsetlist, /* tp_getset */
0, /* tp_base */
0, /* tp_dict */
0, /* tp_descr_get */
0, /* tp_descr_set */
offsetof(partialobject, dict), /* tp_dictoffset */
0, /* tp_init */
0, /* tp_alloc */
partial_new, /* tp_new */
PyObject_GC_Del, /* tp_free */
};
/* reduce (used to be a builtin) ********************************************/
static PyObject *
functools_reduce(PyObject *self, PyObject *args)
{
PyObject *seq, *func, *result = NULL, *it;
if (!PyArg_UnpackTuple(args, "reduce", 2, 3, &func, &seq, &result))
return NULL;
if (result != NULL)
Py_INCREF(result);
it = PyObject_GetIter(seq);
if (it == NULL) {
PyErr_SetString(PyExc_TypeError,
"reduce() arg 2 must support iteration");
Py_XDECREF(result);
return NULL;
}
if ((args = PyTuple_New(2)) == NULL)
goto Fail;
for (;;) {
PyObject *op2;
if (args->ob_refcnt > 1) {
Py_DECREF(args);
if ((args = PyTuple_New(2)) == NULL)
goto Fail;
}
op2 = PyIter_Next(it);
if (op2 == NULL) {
if (PyErr_Occurred())
goto Fail;
break;
}
if (result == NULL)
result = op2;
else {
PyTuple_SetItem(args, 0, result);
PyTuple_SetItem(args, 1, op2);
if ((result = PyEval_CallObject(func, args)) == NULL)
goto Fail;
}
}
Py_DECREF(args);
if (result == NULL)
PyErr_SetString(PyExc_TypeError,
"reduce() of empty sequence with no initial value");
Py_DECREF(it);
return result;
Fail:
Py_XDECREF(args);
Py_XDECREF(result);
Py_DECREF(it);
return NULL;
}
PyDoc_STRVAR(functools_reduce_doc,
"reduce(function, sequence[, initial]) -> value\n\
\n\
Apply a function of two arguments cumulatively to the items of a sequence,\n\
from left to right, so as to reduce the sequence to a single value.\n\
For example, reduce(lambda x, y: x+y, [1, 2, 3, 4, 5]) calculates\n\
((((1+2)+3)+4)+5). If initial is present, it is placed before the items\n\
of the sequence in the calculation, and serves as a default when the\n\
sequence is empty.");
/* module level code ********************************************************/
PyDoc_STRVAR(module_doc,
"Tools that operate on functions.");
static PyMethodDef module_methods[] = {
{"reduce", functools_reduce, METH_VARARGS, functools_reduce_doc},
{NULL, NULL} /* sentinel */
};
static struct PyModuleDef _functoolsmodule = {
PyModuleDef_HEAD_INIT,
"_functools",
module_doc,
-1,
module_methods,
NULL,
NULL,
NULL,
NULL
};
PyMODINIT_FUNC
PyInit__functools(void)
{
int i;
PyObject *m;
char *name;
PyTypeObject *typelist[] = {
&partial_type,
NULL
};
m = PyModule_Create(&_functoolsmodule);
if (m == NULL)
return NULL;
for (i=0 ; typelist[i] != NULL ; i++) {
if (PyType_Ready(typelist[i]) < 0) {
Py_DECREF(m);
return NULL;
}
name = strchr(typelist[i]->tp_name, '.');
assert (name != NULL);
Py_INCREF(typelist[i]);
PyModule_AddObject(m, name+1, (PyObject *)typelist[i]);
}
return m;
}