Modules/operator.c

   1
   2 #include "Python.h"
   3
   4 PyDoc_STRVAR(operator_doc,
   5 "Operator interface.\n\
   6 \n\
   7 This module exports a set of functions implemented in C corresponding\n\
   8 to the intrinsic operators of Python.  For example, operator.add(x, y)\n\
   9 is equivalent to the expression x+y.  The function names are those\n\
  10 used for special class methods; variants without leading and trailing\n\
  11 '__' are also provided for convenience.");
  12
  13 #define spam1(OP,AOP) static PyObject *OP(PyObject *s, PyObject *a1) { \
  14   return AOP(a1); }
  15
  16 #define spam2(OP,AOP) static PyObject *OP(PyObject *s, PyObject *a) { \
  17   PyObject *a1, *a2; \
  18   if(! PyArg_UnpackTuple(a,#OP,2,2,&a1,&a2)) return NULL; \
  19   return AOP(a1,a2); }
  20
  21 #define spamoi(OP,AOP) static PyObject *OP(PyObject *s, PyObject *a) { \
  22   PyObject *a1; int a2; \
  23   if(! PyArg_ParseTuple(a,"Oi:" #OP,&a1,&a2)) return NULL; \
  24   return AOP(a1,a2); }
  25
  26 #define spam2n(OP,AOP) static PyObject *OP(PyObject *s, PyObject *a) { \
  27   PyObject *a1, *a2; \
  28   if(! PyArg_UnpackTuple(a,#OP,2,2,&a1,&a2)) return NULL; \
  29   if(-1 == AOP(a1,a2)) return NULL; \
  30   Py_INCREF(Py_None); \
  31   return Py_None; }
  32
  33 #define spam3n(OP,AOP) static PyObject *OP(PyObject *s, PyObject *a) { \
  34   PyObject *a1, *a2, *a3; \
  35   if(! PyArg_UnpackTuple(a,#OP,3,3,&a1,&a2,&a3)) return NULL; \
  36   if(-1 == AOP(a1,a2,a3)) return NULL; \
  37   Py_INCREF(Py_None); \
  38   return Py_None; }
  39
  40 #define spami(OP,AOP) static PyObject *OP(PyObject *s, PyObject *a1) { \
  41   long r; \
  42   if(-1 == (r=AOP(a1))) return NULL; \
  43   return PyBool_FromLong(r); }
  44
  45 #define spami2(OP,AOP) static PyObject *OP(PyObject *s, PyObject *a) { \
  46   PyObject *a1, *a2; long r; \
  47   if(! PyArg_UnpackTuple(a,#OP,2,2,&a1,&a2)) return NULL; \
  48   if(-1 == (r=AOP(a1,a2))) return NULL; \
  49   return PyInt_FromLong(r); }
  50
  51 #define spamn2(OP,AOP) static PyObject *OP(PyObject *s, PyObject *a) { \
  52   PyObject *a1, *a2; Py_ssize_t r; \
  53   if(! PyArg_UnpackTuple(a,#OP,2,2,&a1,&a2)) return NULL; \
  54   if(-1 == (r=AOP(a1,a2))) return NULL; \
  55   return PyInt_FromSsize_t(r); }
  56
  57 #define spami2b(OP,AOP) static PyObject *OP(PyObject *s, PyObject *a) { \
  58   PyObject *a1, *a2; long r; \
  59   if(! PyArg_UnpackTuple(a,#OP,2,2,&a1,&a2)) return NULL; \
  60   if(-1 == (r=AOP(a1,a2))) return NULL; \
  61   return PyBool_FromLong(r); }
  62
  63 #define spamrc(OP,A) static PyObject *OP(PyObject *s, PyObject *a) { \
  64   PyObject *a1, *a2; \
  65   if(! PyArg_UnpackTuple(a,#OP,2,2,&a1,&a2)) return NULL; \
  66   return PyObject_RichCompare(a1,a2,A); }
  67
  68 spami(isCallable       , PyCallable_Check)
  69 spami(isNumberType     , PyNumber_Check)
  70 spami(truth            , PyObject_IsTrue)
  71 spam2(op_add           , PyNumber_Add)
  72 spam2(op_sub           , PyNumber_Subtract)
  73 spam2(op_mul           , PyNumber_Multiply)
  74 spam2(op_div           , PyNumber_Divide)
  75 spam2(op_floordiv      , PyNumber_FloorDivide)
  76 spam2(op_truediv       , PyNumber_TrueDivide)
  77 spam2(op_mod           , PyNumber_Remainder)
  78 spam1(op_neg           , PyNumber_Negative)
  79 spam1(op_pos           , PyNumber_Positive)
  80 spam1(op_abs           , PyNumber_Absolute)
  81 spam1(op_inv           , PyNumber_Invert)
  82 spam1(op_invert        , PyNumber_Invert)
  83 spam2(op_lshift        , PyNumber_Lshift)
  84 spam2(op_rshift        , PyNumber_Rshift)
  85 spami(op_not_          , PyObject_Not)
  86 spam2(op_and_          , PyNumber_And)
  87 spam2(op_xor           , PyNumber_Xor)
  88 spam2(op_or_           , PyNumber_Or)
  89 spam2(op_iadd          , PyNumber_InPlaceAdd)
  90 spam2(op_isub          , PyNumber_InPlaceSubtract)
  91 spam2(op_imul          , PyNumber_InPlaceMultiply)
  92 spam2(op_idiv          , PyNumber_InPlaceDivide)
  93 spam2(op_ifloordiv     , PyNumber_InPlaceFloorDivide)
  94 spam2(op_itruediv      , PyNumber_InPlaceTrueDivide)
  95 spam2(op_imod          , PyNumber_InPlaceRemainder)
  96 spam2(op_ilshift       , PyNumber_InPlaceLshift)
  97 spam2(op_irshift       , PyNumber_InPlaceRshift)
  98 spam2(op_iand          , PyNumber_InPlaceAnd)
  99 spam2(op_ixor          , PyNumber_InPlaceXor)
 100 spam2(op_ior           , PyNumber_InPlaceOr)
 101 spami(isSequenceType   , PySequence_Check)
 102 spam2(op_concat        , PySequence_Concat)
 103 spamoi(op_repeat       , PySequence_Repeat)
 104 spam2(op_iconcat       , PySequence_InPlaceConcat)
 105 spamoi(op_irepeat      , PySequence_InPlaceRepeat)
 106 spami2b(op_contains     , PySequence_Contains)
 107 spami2b(sequenceIncludes, PySequence_Contains)
 108 spamn2(indexOf         , PySequence_Index)
 109 spamn2(countOf         , PySequence_Count)
 110 spami(isMappingType    , PyMapping_Check)
 111 spam2(op_getitem       , PyObject_GetItem)
 112 spam2n(op_delitem       , PyObject_DelItem)
 113 spam3n(op_setitem      , PyObject_SetItem)
 114 spamrc(op_lt           , Py_LT)
 115 spamrc(op_le           , Py_LE)
 116 spamrc(op_eq           , Py_EQ)
 117 spamrc(op_ne           , Py_NE)
 118 spamrc(op_gt           , Py_GT)
 119 spamrc(op_ge           , Py_GE)
 120
 121 static PyObject*
 122 op_pow(PyObject *s, PyObject *a)
 123 {
 124         PyObject *a1, *a2;
 125         if (PyArg_UnpackTuple(a,"pow", 2, 2, &a1, &a2))
 126                 return PyNumber_Power(a1, a2, Py_None);
 127         return NULL;
 128 }
 129
 130 static PyObject*
 131 op_ipow(PyObject *s, PyObject *a)
 132 {
 133         PyObject *a1, *a2;
 134         if (PyArg_UnpackTuple(a,"ipow", 2, 2, &a1, &a2))
 135                 return PyNumber_InPlacePower(a1, a2, Py_None);
 136         return NULL;
 137 }
 138
 139 static PyObject *
 140 op_index(PyObject *s, PyObject *a)
 141 {
 142         Py_ssize_t i;
 143         PyObject *a1;
 144         if (!PyArg_UnpackTuple(a,"index", 1, 1, &a1))
 145                 return NULL;
 146         i = PyNumber_Index(a1);
 147         if (i == -1 && PyErr_Occurred())
 148                 return NULL;
 149         else
 150                 return PyInt_FromSsize_t(i);
 151 }
 152
 153 static PyObject*
 154 is_(PyObject *s, PyObject *a)
 155 {
 156         PyObject *a1, *a2, *result = NULL;
 157         if (PyArg_UnpackTuple(a,"is_", 2, 2, &a1, &a2)) {
 158                 result = (a1 == a2) ? Py_True : Py_False;
 159                 Py_INCREF(result);
 160         }
 161         return result;
 162 }
 163
 164 static PyObject*
 165 is_not(PyObject *s, PyObject *a)
 166 {
 167         PyObject *a1, *a2, *result = NULL;
 168         if (PyArg_UnpackTuple(a,"is_not", 2, 2, &a1, &a2)) {
 169                 result = (a1 != a2) ? Py_True : Py_False;
 170                 Py_INCREF(result);
 171         }
 172         return result;
 173 }
 174
 175 static PyObject*
 176 op_getslice(PyObject *s, PyObject *a)
 177 {
 178         PyObject *a1;
 179         int a2,a3;
 180
 181         if (!PyArg_ParseTuple(a,"Oii:getslice",&a1,&a2,&a3))
 182                 return NULL;
 183         return PySequence_GetSlice(a1,a2,a3);
 184 }
 185
 186 static PyObject*
 187 op_setslice(PyObject *s, PyObject *a)
 188 {
 189         PyObject *a1, *a4;
 190         int a2,a3;
 191
 192         if (!PyArg_ParseTuple(a,"OiiO:setslice",&a1,&a2,&a3,&a4))
 193                 return NULL;
 194
 195         if (-1 == PySequence_SetSlice(a1,a2,a3,a4))
 196                 return NULL;
 197
 198         Py_INCREF(Py_None);
 199         return Py_None;
 200 }
 201
 202 static PyObject*
 203 op_delslice(PyObject *s, PyObject *a)
 204 {
 205         PyObject *a1;
 206         int a2,a3;
 207
 208         if(! PyArg_ParseTuple(a,"Oii:delslice",&a1,&a2,&a3))
 209                 return NULL;
 210
 211         if (-1 == PySequence_DelSlice(a1,a2,a3))
 212                 return NULL;
 213
 214         Py_INCREF(Py_None);
 215         return Py_None;
 216 }
 217
 218 #undef spam1
 219 #undef spam2
 220 #undef spam1o
 221 #undef spam1o
 222 #define spam1(OP,DOC) {#OP, OP, METH_VARARGS, PyDoc_STR(DOC)},
 223 #define spam2(OP,ALTOP,DOC) {#OP, op_##OP, METH_VARARGS, PyDoc_STR(DOC)}, \
 224                            {#ALTOP, op_##OP, METH_VARARGS, PyDoc_STR(DOC)},
 225 #define spam1o(OP,DOC) {#OP, OP, METH_O, PyDoc_STR(DOC)},
 226 #define spam2o(OP,ALTOP,DOC) {#OP, op_##OP, METH_O, PyDoc_STR(DOC)}, \
 227                            {#ALTOP, op_##OP, METH_O, PyDoc_STR(DOC)},
 228
 229 static struct PyMethodDef operator_methods[] = {
 230
 231 spam1o(isCallable,
 232  "isCallable(a) -- Same as callable(a).")
 233 spam1o(isNumberType,
 234  "isNumberType(a) -- Return True if a has a numeric type, False otherwise.")
 235 spam1o(isSequenceType,
 236  "isSequenceType(a) -- Return True if a has a sequence type, False otherwise.")
 237 spam1o(truth,
 238  "truth(a) -- Return True if a is true, False otherwise.")
 239 spam2(contains,__contains__,
 240  "contains(a, b) -- Same as b in a (note reversed operands).")
 241 spam1(sequenceIncludes,
 242  "sequenceIncludes(a, b) -- Same as b in a (note reversed operands; deprecated).")
 243 spam1(indexOf,
 244  "indexOf(a, b) -- Return the first index of b in a.")
 245 spam1(countOf,
 246  "countOf(a, b) -- Return the number of times b occurs in a.")
 247 spam1o(isMappingType,
 248  "isMappingType(a) -- Return True if a has a mapping type, False otherwise.")
 249
 250 spam1(is_, "is_(a, b) -- Same as a is b.")
 251 spam1(is_not, "is_not(a, b) -- Same as a is not b.")
 252 spam2(index, __index__, "index(a) -- Same as a.__index__()")
 253 spam2(add,__add__, "add(a, b) -- Same as a + b.")
 254 spam2(sub,__sub__, "sub(a, b) -- Same as a - b.")
 255 spam2(mul,__mul__, "mul(a, b) -- Same as a * b.")
 256 spam2(div,__div__, "div(a, b) -- Same as a / b when __future__.division is not in effect.")
 257 spam2(floordiv,__floordiv__, "floordiv(a, b) -- Same as a // b.")
 258 spam2(truediv,__truediv__, "truediv(a, b) -- Same as a / b when __future__.division is in effect.")
 259 spam2(mod,__mod__, "mod(a, b) -- Same as a % b.")
 260 spam2o(neg,__neg__, "neg(a) -- Same as -a.")
 261 spam2o(pos,__pos__, "pos(a) -- Same as +a.")
 262 spam2o(abs,__abs__, "abs(a) -- Same as abs(a).")
 263 spam2o(inv,__inv__, "inv(a) -- Same as ~a.")
 264 spam2o(invert,__invert__, "invert(a) -- Same as ~a.")
 265 spam2(lshift,__lshift__, "lshift(a, b) -- Same as a << b.")
 266 spam2(rshift,__rshift__, "rshift(a, b) -- Same as a >> b.")
 267 spam2o(not_,__not__, "not_(a) -- Same as not a.")
 268 spam2(and_,__and__, "and_(a, b) -- Same as a & b.")
 269 spam2(xor,__xor__, "xor(a, b) -- Same as a ^ b.")
 270 spam2(or_,__or__, "or_(a, b) -- Same as a | b.")
 271 spam2(iadd,__iadd__, "iadd(a, b) -- Same as a += b.")
 272 spam2(isub,__isub__, "isub(a, b) -- Same as a -= b.")
 273 spam2(imul,__imul__, "imul(a, b) -- Same as a *= b.")
 274 spam2(idiv,__idiv__, "idiv(a, b) -- Same as a /= b when __future__.division is not in effect.")
 275 spam2(ifloordiv,__ifloordiv__, "ifloordiv(a, b) -- Same as a //= b.")
 276 spam2(itruediv,__itruediv__, "itruediv(a, b) -- Same as a /= b when __future__.division is in effect.")
 277 spam2(imod,__imod__, "imod(a, b) -- Same as a %= b.")
 278 spam2(ilshift,__ilshift__, "ilshift(a, b) -- Same as a <<= b.")
 279 spam2(irshift,__irshift__, "irshift(a, b) -- Same as a >>= b.")
 280 spam2(iand,__iand__, "iand(a, b) -- Same as a &= b.")
 281 spam2(ixor,__ixor__, "ixor(a, b) -- Same as a ^= b.")
 282 spam2(ior,__ior__, "ior(a, b) -- Same as a |= b.")
 283 spam2(concat,__concat__,
 284  "concat(a, b) -- Same as a + b, for a and b sequences.")
 285 spam2(repeat,__repeat__,
 286  "repeat(a, b) -- Return a * b, where a is a sequence, and b is an integer.")
 287 spam2(iconcat,__iconcat__,
 288  "iconcat(a, b) -- Same as a += b, for a and b sequences.")
 289 spam2(irepeat,__irepeat__,
 290  "irepeat(a, b) -- Same as a *= b, where a is a sequence, and b is an integer.")
 291 spam2(getitem,__getitem__,
 292  "getitem(a, b) -- Same as a[b].")
 293 spam2(setitem,__setitem__,
 294  "setitem(a, b, c) -- Same as a[b] = c.")
 295 spam2(delitem,__delitem__,
 296  "delitem(a, b) -- Same as del a[b].")
 297 spam2(pow,__pow__, "pow(a, b) -- Same as a ** b.")
 298 spam2(ipow,__ipow__, "ipow(a, b) -- Same as a **= b.")
 299 spam2(getslice,__getslice__,
 300  "getslice(a, b, c) -- Same as a[b:c].")
 301 spam2(setslice,__setslice__,
 302 "setslice(a, b, c, d) -- Same as a[b:c] = d.")
 303 spam2(delslice,__delslice__,
 304 "delslice(a, b, c) -- Same as del a[b:c].")
 305 spam2(lt,__lt__, "lt(a, b) -- Same as a<b.")
 306 spam2(le,__le__, "le(a, b) -- Same as a<=b.")
 307 spam2(eq,__eq__, "eq(a, b) -- Same as a==b.")
 308 spam2(ne,__ne__, "ne(a, b) -- Same as a!=b.")
 309 spam2(gt,__gt__, "gt(a, b) -- Same as a>b.")
 310 spam2(ge,__ge__, "ge(a, b) -- Same as a>=b.")
 311
 312         {NULL,          NULL}           /* sentinel */
 313
 314 };
 315
 316 /* itemgetter object **********************************************************/
 317
 318 typedef struct {
 319         PyObject_HEAD
 320         Py_ssize_t nitems;
 321         PyObject *item;
 322 } itemgetterobject;
 323
 324 static PyTypeObject itemgetter_type;
 325
 326 static PyObject *
 327 itemgetter_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
 328 {
 329         itemgetterobject *ig;
 330         PyObject *item;
 331         Py_ssize_t nitems;
 332
 333         if (!_PyArg_NoKeywords("itemgetter()", kwds))
 334                 return NULL;
 335
 336         nitems = PyTuple_GET_SIZE(args);
 337         if (nitems <= 1) {
 338                 if (!PyArg_UnpackTuple(args, "itemgetter", 1, 1, &item))
 339                         return NULL;
 340         } else
 341                 item = args;
 342
 343         /* create itemgetterobject structure */
 344         ig = PyObject_GC_New(itemgetterobject, &itemgetter_type);
 345         if (ig == NULL)
 346                 return NULL;
 347
 348         Py_INCREF(item);
 349         ig->item = item;
 350         ig->nitems = nitems;
 351
 352         PyObject_GC_Track(ig);
 353         return (PyObject *)ig;
 354 }
 355
 356 static void
 357 itemgetter_dealloc(itemgetterobject *ig)
 358 {
 359         PyObject_GC_UnTrack(ig);
 360         Py_XDECREF(ig->item);
 361         PyObject_GC_Del(ig);
 362 }
 363
 364 static int
 365 itemgetter_traverse(itemgetterobject *ig, visitproc visit, void *arg)
 366 {
 367         Py_VISIT(ig->item);
 368         return 0;
 369 }
 370
 371 static PyObject *
 372 itemgetter_call(itemgetterobject *ig, PyObject *args, PyObject *kw)
 373 {
 374         PyObject *obj, *result;
 375         Py_ssize_t i, nitems=ig->nitems;
 376
 377         if (!PyArg_UnpackTuple(args, "itemgetter", 1, 1, &obj))
 378                 return NULL;
 379         if (nitems == 1)
 380                 return PyObject_GetItem(obj, ig->item);
 381
 382         assert(PyTuple_Check(ig->item));
 383         assert(PyTuple_GET_SIZE(ig->item) == nitems);
 384
 385         result = PyTuple_New(nitems);
 386         if (result == NULL)
 387                 return NULL;
 388
 389         for (i=0 ; i < nitems ; i++) {
 390                 PyObject *item, *val;
 391                 item = PyTuple_GET_ITEM(ig->item, i);
 392                 val = PyObject_GetItem(obj, item);
 393                 if (val == NULL) {
 394                         Py_DECREF(result);
 395                         return NULL;
 396                 }
 397                 PyTuple_SET_ITEM(result, i, val);
 398         }
 399         return result;
 400 }
 401
 402 PyDoc_STRVAR(itemgetter_doc,
 403 "itemgetter(item, ...) --> itemgetter object\n\
 404 \n\
 405 Return a callable object that fetches the given item(s) from its operand.\n\
 406 After, f=itemgetter(2), the call f(r) returns r[2].\n\
 407 After, g=itemgetter(2,5,3), the call g(r) returns (r[2], r[5], r[3])");
 408
 409 static PyTypeObject itemgetter_type = {
 410         PyObject_HEAD_INIT(NULL)
 411         0,                              /* ob_size */
 412         "operator.itemgetter",          /* tp_name */
 413         sizeof(itemgetterobject),       /* tp_basicsize */
 414         0,                              /* tp_itemsize */
 415         /* methods */
 416         (destructor)itemgetter_dealloc, /* tp_dealloc */
 417         0,                              /* tp_print */
 418         0,                              /* tp_getattr */
 419         0,                              /* tp_setattr */
 420         0,                              /* tp_compare */
 421         0,                              /* tp_repr */
 422         0,                              /* tp_as_number */
 423         0,                              /* tp_as_sequence */
 424         0,                              /* tp_as_mapping */
 425         0,                              /* tp_hash */
 426         (ternaryfunc)itemgetter_call,   /* tp_call */
 427         0,                              /* tp_str */
 428         PyObject_GenericGetAttr,        /* tp_getattro */
 429         0,                              /* tp_setattro */
 430         0,                              /* tp_as_buffer */
 431         Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,        /* tp_flags */
 432         itemgetter_doc,                 /* tp_doc */
 433         (traverseproc)itemgetter_traverse,      /* tp_traverse */
 434         0,                              /* tp_clear */
 435         0,                              /* tp_richcompare */
 436         0,                              /* tp_weaklistoffset */
 437         0,                              /* tp_iter */
 438         0,                              /* tp_iternext */
 439         0,                              /* tp_methods */
 440         0,                              /* tp_members */
 441         0,                              /* tp_getset */
 442         0,                              /* tp_base */
 443         0,                              /* tp_dict */
 444         0,                              /* tp_descr_get */
 445         0,                              /* tp_descr_set */
 446         0,                              /* tp_dictoffset */
 447         0,                              /* tp_init */
 448         0,                              /* tp_alloc */
 449         itemgetter_new,                 /* tp_new */
 450         0,                              /* tp_free */
 451 };
 452
 453
 454 /* attrgetter object **********************************************************/
 455
 456 typedef struct {
 457         PyObject_HEAD
 458         Py_ssize_t nattrs;
 459         PyObject *attr;
 460 } attrgetterobject;
 461
 462 static PyTypeObject attrgetter_type;
 463
 464 static PyObject *
 465 attrgetter_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
 466 {
 467         attrgetterobject *ag;
 468         PyObject *attr;
 469         Py_ssize_t nattrs;
 470
 471         if (!_PyArg_NoKeywords("attrgetter()", kwds))
 472                 return NULL;
 473
 474         nattrs = PyTuple_GET_SIZE(args);
 475         if (nattrs <= 1) {
 476                 if (!PyArg_UnpackTuple(args, "attrgetter", 1, 1, &attr))
 477                         return NULL;
 478         } else
 479                 attr = args;
 480
 481         /* create attrgetterobject structure */
 482         ag = PyObject_GC_New(attrgetterobject, &attrgetter_type);
 483         if (ag == NULL)
 484                 return NULL;
 485
 486         Py_INCREF(attr);
 487         ag->attr = attr;
 488         ag->nattrs = nattrs;
 489
 490         PyObject_GC_Track(ag);
 491         return (PyObject *)ag;
 492 }
 493
 494 static void
 495 attrgetter_dealloc(attrgetterobject *ag)
 496 {
 497         PyObject_GC_UnTrack(ag);
 498         Py_XDECREF(ag->attr);
 499         PyObject_GC_Del(ag);
 500 }
 501
 502 static int
 503 attrgetter_traverse(attrgetterobject *ag, visitproc visit, void *arg)
 504 {
 505         Py_VISIT(ag->attr);
 506         return 0;
 507 }
 508
 509 static PyObject *
 510 attrgetter_call(attrgetterobject *ag, PyObject *args, PyObject *kw)
 511 {
 512         PyObject *obj, *result;
 513         Py_ssize_t i, nattrs=ag->nattrs;
 514
 515         if (!PyArg_UnpackTuple(args, "attrgetter", 1, 1, &obj))
 516                 return NULL;
 517         if (ag->nattrs == 1)
 518                 return PyObject_GetAttr(obj, ag->attr);
 519
 520         assert(PyTuple_Check(ag->attr));
 521         assert(PyTuple_GET_SIZE(ag->attr) == nattrs);
 522
 523         result = PyTuple_New(nattrs);
 524         if (result == NULL)
 525                 return NULL;
 526
 527         for (i=0 ; i < nattrs ; i++) {
 528                 PyObject *attr, *val;
 529                 attr = PyTuple_GET_ITEM(ag->attr, i);
 530                 val = PyObject_GetAttr(obj, attr);
 531                 if (val == NULL) {
 532                         Py_DECREF(result);
 533                         return NULL;
 534                 }
 535                 PyTuple_SET_ITEM(result, i, val);
 536         }
 537         return result;
 538 }
 539
 540 PyDoc_STRVAR(attrgetter_doc,
 541 "attrgetter(attr, ...) --> attrgetter object\n\
 542 \n\
 543 Return a callable object that fetches the given attribute(s) from its operand.\n\
 544 After, f=attrgetter('name'), the call f(r) returns r.name.\n\
 545 After, g=attrgetter('name', 'date'), the call g(r) returns (r.name, r.date).");
 546
 547 static PyTypeObject attrgetter_type = {
 548         PyObject_HEAD_INIT(NULL)
 549         0,                              /* ob_size */
 550         "operator.attrgetter",          /* tp_name */
 551         sizeof(attrgetterobject),       /* tp_basicsize */
 552         0,                              /* tp_itemsize */
 553         /* methods */
 554         (destructor)attrgetter_dealloc, /* tp_dealloc */
 555         0,                              /* tp_print */
 556         0,                              /* tp_getattr */
 557         0,                              /* tp_setattr */
 558         0,                              /* tp_compare */
 559         0,                              /* tp_repr */
 560         0,                              /* tp_as_number */
 561         0,                              /* tp_as_sequence */
 562         0,                              /* tp_as_mapping */
 563         0,                              /* tp_hash */
 564         (ternaryfunc)attrgetter_call,   /* tp_call */
 565         0,                              /* tp_str */
 566         PyObject_GenericGetAttr,        /* tp_getattro */
 567         0,                              /* tp_setattro */
 568         0,                              /* tp_as_buffer */
 569         Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,        /* tp_flags */
 570         attrgetter_doc,                 /* tp_doc */
 571         (traverseproc)attrgetter_traverse,      /* tp_traverse */
 572         0,                              /* tp_clear */
 573         0,                              /* tp_richcompare */
 574         0,                              /* tp_weaklistoffset */
 575         0,                              /* tp_iter */
 576         0,                              /* tp_iternext */
 577         0,                              /* tp_methods */
 578         0,                              /* tp_members */
 579         0,                              /* tp_getset */
 580         0,                              /* tp_base */
 581         0,                              /* tp_dict */
 582         0,                              /* tp_descr_get */
 583         0,                              /* tp_descr_set */
 584         0,                              /* tp_dictoffset */
 585         0,                              /* tp_init */
 586         0,                              /* tp_alloc */
 587         attrgetter_new,                 /* tp_new */
 588         0,                              /* tp_free */
 589 };
 590 /* Initialization function for the module (*must* be called initoperator) */
 591
 592 PyMODINIT_FUNC
 593 initoperator(void)
 594 {
 595         PyObject *m;
 596
 597         /* Create the module and add the functions */
 598         m = Py_InitModule4("operator", operator_methods, operator_doc,
 599                        (PyObject*)NULL, PYTHON_API_VERSION);
 600         if (m == NULL)
 601                 return;
 602
 603         if (PyType_Ready(&itemgetter_type) < 0)
 604                 return;
 605         Py_INCREF(&itemgetter_type);
 606         PyModule_AddObject(m, "itemgetter", (PyObject *)&itemgetter_type);
 607
 608         if (PyType_Ready(&attrgetter_type) < 0)
 609                 return;
 610         Py_INCREF(&attrgetter_type);
 611         PyModule_AddObject(m, "attrgetter", (PyObject *)&attrgetter_type);
 612 }