blob: 54abb89d81de235a0397df37e00f287e3f031850 [file] [log] [blame]
Raymond Hettinger9c323f82005-02-28 19:39:44 +00001
2#include "Python.h"
3#include "structmember.h"
4
Nick Coghlanc649ec52006-05-29 12:43:05 +00005/* _functools module written and maintained
Raymond Hettinger9c323f82005-02-28 19:39:44 +00006 by Hye-Shik Chang <perky@FreeBSD.org>
7 with adaptations by Raymond Hettinger <python@rcn.com>
Nick Coghlanc649ec52006-05-29 12:43:05 +00008 Copyright (c) 2004, 2005, 2006 Python Software Foundation.
Raymond Hettinger9c323f82005-02-28 19:39:44 +00009 All rights reserved.
10*/
11
12/* partial object **********************************************************/
13
14typedef struct {
15 PyObject_HEAD
16 PyObject *fn;
17 PyObject *args;
18 PyObject *kw;
Raymond Hettingerc8b6d1b2005-03-08 06:14:50 +000019 PyObject *dict;
20 PyObject *weakreflist; /* List of weak references */
Raymond Hettinger9c323f82005-02-28 19:39:44 +000021} partialobject;
22
23static PyTypeObject partial_type;
24
25static PyObject *
26partial_new(PyTypeObject *type, PyObject *args, PyObject *kw)
27{
28 PyObject *func;
29 partialobject *pto;
30
31 if (PyTuple_GET_SIZE(args) < 1) {
32 PyErr_SetString(PyExc_TypeError,
33 "type 'partial' takes at least one argument");
34 return NULL;
35 }
36
37 func = PyTuple_GET_ITEM(args, 0);
38 if (!PyCallable_Check(func)) {
39 PyErr_SetString(PyExc_TypeError,
40 "the first argument must be callable");
41 return NULL;
42 }
43
44 /* create partialobject structure */
45 pto = (partialobject *)type->tp_alloc(type, 0);
46 if (pto == NULL)
47 return NULL;
48
49 pto->fn = func;
50 Py_INCREF(func);
Martin v. Löwisb1ed7fa2006-04-13 07:52:27 +000051 pto->args = PyTuple_GetSlice(args, 1, PY_SSIZE_T_MAX);
Raymond Hettinger9c323f82005-02-28 19:39:44 +000052 if (pto->args == NULL) {
53 pto->kw = NULL;
54 Py_DECREF(pto);
55 return NULL;
56 }
57 if (kw != NULL) {
58 pto->kw = PyDict_Copy(kw);
59 if (pto->kw == NULL) {
60 Py_DECREF(pto);
61 return NULL;
62 }
63 } else {
64 pto->kw = Py_None;
65 Py_INCREF(Py_None);
66 }
67
Raymond Hettingerc8b6d1b2005-03-08 06:14:50 +000068 pto->weakreflist = NULL;
69 pto->dict = NULL;
70
Raymond Hettinger9c323f82005-02-28 19:39:44 +000071 return (PyObject *)pto;
72}
73
74static void
75partial_dealloc(partialobject *pto)
76{
77 PyObject_GC_UnTrack(pto);
Raymond Hettingerc8b6d1b2005-03-08 06:14:50 +000078 if (pto->weakreflist != NULL)
79 PyObject_ClearWeakRefs((PyObject *) pto);
Raymond Hettinger9c323f82005-02-28 19:39:44 +000080 Py_XDECREF(pto->fn);
81 Py_XDECREF(pto->args);
82 Py_XDECREF(pto->kw);
Raymond Hettingerc8b6d1b2005-03-08 06:14:50 +000083 Py_XDECREF(pto->dict);
Raymond Hettinger9c323f82005-02-28 19:39:44 +000084 pto->ob_type->tp_free(pto);
85}
86
87static PyObject *
88partial_call(partialobject *pto, PyObject *args, PyObject *kw)
89{
90 PyObject *ret;
91 PyObject *argappl = NULL, *kwappl = NULL;
92
93 assert (PyCallable_Check(pto->fn));
94 assert (PyTuple_Check(pto->args));
95 assert (pto->kw == Py_None || PyDict_Check(pto->kw));
96
97 if (PyTuple_GET_SIZE(pto->args) == 0) {
98 argappl = args;
99 Py_INCREF(args);
100 } else if (PyTuple_GET_SIZE(args) == 0) {
101 argappl = pto->args;
102 Py_INCREF(pto->args);
103 } else {
104 argappl = PySequence_Concat(pto->args, args);
105 if (argappl == NULL)
106 return NULL;
107 }
108
109 if (pto->kw == Py_None) {
110 kwappl = kw;
111 Py_XINCREF(kw);
112 } else {
113 kwappl = PyDict_Copy(pto->kw);
114 if (kwappl == NULL) {
115 Py_DECREF(argappl);
116 return NULL;
117 }
118 if (kw != NULL) {
119 if (PyDict_Merge(kwappl, kw, 1) != 0) {
120 Py_DECREF(argappl);
121 Py_DECREF(kwappl);
122 return NULL;
123 }
124 }
125 }
126
127 ret = PyObject_Call(pto->fn, argappl, kwappl);
128 Py_DECREF(argappl);
129 Py_XDECREF(kwappl);
130 return ret;
131}
132
133static int
134partial_traverse(partialobject *pto, visitproc visit, void *arg)
135{
136 Py_VISIT(pto->fn);
137 Py_VISIT(pto->args);
138 Py_VISIT(pto->kw);
Raymond Hettingerc8b6d1b2005-03-08 06:14:50 +0000139 Py_VISIT(pto->dict);
Raymond Hettinger9c323f82005-02-28 19:39:44 +0000140 return 0;
141}
142
143PyDoc_STRVAR(partial_doc,
144"partial(func, *args, **keywords) - new function with partial application\n\
145 of the given arguments and keywords.\n");
146
147#define OFF(x) offsetof(partialobject, x)
148static PyMemberDef partial_memberlist[] = {
149 {"func", T_OBJECT, OFF(fn), READONLY,
150 "function object to use in future partial calls"},
151 {"args", T_OBJECT, OFF(args), READONLY,
152 "tuple of arguments to future partial calls"},
153 {"keywords", T_OBJECT, OFF(kw), READONLY,
154 "dictionary of keyword arguments to future partial calls"},
155 {NULL} /* Sentinel */
156};
157
Raymond Hettingerc8b6d1b2005-03-08 06:14:50 +0000158static PyObject *
159partial_get_dict(partialobject *pto)
160{
161 if (pto->dict == NULL) {
162 pto->dict = PyDict_New();
163 if (pto->dict == NULL)
164 return NULL;
165 }
166 Py_INCREF(pto->dict);
167 return pto->dict;
168}
169
170static int
171partial_set_dict(partialobject *pto, PyObject *value)
172{
173 PyObject *tmp;
174
175 /* It is illegal to del p.__dict__ */
176 if (value == NULL) {
177 PyErr_SetString(PyExc_TypeError,
178 "a partial object's dictionary may not be deleted");
179 return -1;
180 }
181 /* Can only set __dict__ to a dictionary */
182 if (!PyDict_Check(value)) {
183 PyErr_SetString(PyExc_TypeError,
184 "setting partial object's dictionary to a non-dict");
185 return -1;
186 }
187 tmp = pto->dict;
188 Py_INCREF(value);
189 pto->dict = value;
190 Py_XDECREF(tmp);
191 return 0;
192}
193
Georg Brandlc2fb6c72006-02-21 17:49:57 +0000194static PyGetSetDef partial_getsetlist[] = {
Raymond Hettingerc8b6d1b2005-03-08 06:14:50 +0000195 {"__dict__", (getter)partial_get_dict, (setter)partial_set_dict},
196 {NULL} /* Sentinel */
197};
198
Raymond Hettinger9c323f82005-02-28 19:39:44 +0000199static PyTypeObject partial_type = {
200 PyObject_HEAD_INIT(NULL)
201 0, /* ob_size */
Nick Coghlanc649ec52006-05-29 12:43:05 +0000202 "functools.partial", /* tp_name */
Raymond Hettinger9c323f82005-02-28 19:39:44 +0000203 sizeof(partialobject), /* tp_basicsize */
204 0, /* tp_itemsize */
205 /* methods */
206 (destructor)partial_dealloc, /* tp_dealloc */
207 0, /* tp_print */
208 0, /* tp_getattr */
209 0, /* tp_setattr */
210 0, /* tp_compare */
211 0, /* tp_repr */
212 0, /* tp_as_number */
213 0, /* tp_as_sequence */
214 0, /* tp_as_mapping */
215 0, /* tp_hash */
216 (ternaryfunc)partial_call, /* tp_call */
217 0, /* tp_str */
218 PyObject_GenericGetAttr, /* tp_getattro */
Raymond Hettingerc8b6d1b2005-03-08 06:14:50 +0000219 PyObject_GenericSetAttr, /* tp_setattro */
Raymond Hettinger9c323f82005-02-28 19:39:44 +0000220 0, /* tp_as_buffer */
221 Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC |
Raymond Hettingerc8b6d1b2005-03-08 06:14:50 +0000222 Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_WEAKREFS, /* tp_flags */
Raymond Hettinger9c323f82005-02-28 19:39:44 +0000223 partial_doc, /* tp_doc */
224 (traverseproc)partial_traverse, /* tp_traverse */
225 0, /* tp_clear */
226 0, /* tp_richcompare */
Raymond Hettingerc8b6d1b2005-03-08 06:14:50 +0000227 offsetof(partialobject, weakreflist), /* tp_weaklistoffset */
Raymond Hettinger9c323f82005-02-28 19:39:44 +0000228 0, /* tp_iter */
229 0, /* tp_iternext */
230 0, /* tp_methods */
231 partial_memberlist, /* tp_members */
Georg Brandlc2fb6c72006-02-21 17:49:57 +0000232 partial_getsetlist, /* tp_getset */
Raymond Hettinger9c323f82005-02-28 19:39:44 +0000233 0, /* tp_base */
234 0, /* tp_dict */
235 0, /* tp_descr_get */
236 0, /* tp_descr_set */
Raymond Hettingerc8b6d1b2005-03-08 06:14:50 +0000237 offsetof(partialobject, dict), /* tp_dictoffset */
Raymond Hettinger9c323f82005-02-28 19:39:44 +0000238 0, /* tp_init */
239 0, /* tp_alloc */
240 partial_new, /* tp_new */
241 PyObject_GC_Del, /* tp_free */
242};
243
244
245/* module level code ********************************************************/
246
247PyDoc_STRVAR(module_doc,
Nick Coghlanc649ec52006-05-29 12:43:05 +0000248"Tools that operate on functions.");
Raymond Hettinger9c323f82005-02-28 19:39:44 +0000249
250static PyMethodDef module_methods[] = {
251 {NULL, NULL} /* sentinel */
252};
253
254PyMODINIT_FUNC
Nick Coghlanc649ec52006-05-29 12:43:05 +0000255init_functools(void)
Raymond Hettinger9c323f82005-02-28 19:39:44 +0000256{
257 int i;
258 PyObject *m;
259 char *name;
260 PyTypeObject *typelist[] = {
261 &partial_type,
262 NULL
263 };
264
Nick Coghlanc649ec52006-05-29 12:43:05 +0000265 m = Py_InitModule3("_functools", module_methods, module_doc);
Neal Norwitz1ac754f2006-01-19 06:09:39 +0000266 if (m == NULL)
267 return;
Raymond Hettinger9c323f82005-02-28 19:39:44 +0000268
269 for (i=0 ; typelist[i] != NULL ; i++) {
270 if (PyType_Ready(typelist[i]) < 0)
271 return;
272 name = strchr(typelist[i]->tp_name, '.');
273 assert (name != NULL);
274 Py_INCREF(typelist[i]);
275 PyModule_AddObject(m, name+1, (PyObject *)typelist[i]);
276 }
277}