ref: 2c9e3861a54e22498fb2e3226defe4393b20b202
dir: /sys/src/cmd/python/Objects/boolobject.c/
/* Boolean type, a subtype of int */
#include "Python.h"
/* We need to define bool_print to override int_print */
static int
bool_print(PyBoolObject *self, FILE *fp, int flags)
{
fputs(self->ob_ival == 0 ? "False" : "True", fp);
return 0;
}
/* We define bool_repr to return "False" or "True" */
static PyObject *false_str = NULL;
static PyObject *true_str = NULL;
static PyObject *
bool_repr(PyBoolObject *self)
{
PyObject *s;
if (self->ob_ival)
s = true_str ? true_str :
(true_str = PyString_InternFromString("True"));
else
s = false_str ? false_str :
(false_str = PyString_InternFromString("False"));
Py_XINCREF(s);
return s;
}
/* Function to return a bool from a C long */
PyObject *PyBool_FromLong(long ok)
{
PyObject *result;
if (ok)
result = Py_True;
else
result = Py_False;
Py_INCREF(result);
return result;
}
/* We define bool_new to always return either Py_True or Py_False */
static PyObject *
bool_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
{
static char *kwlist[] = {"x", 0};
PyObject *x = Py_False;
long ok;
if (!PyArg_ParseTupleAndKeywords(args, kwds, "|O:bool", kwlist, &x))
return NULL;
ok = PyObject_IsTrue(x);
if (ok < 0)
return NULL;
return PyBool_FromLong(ok);
}
/* Arithmetic operations redefined to return bool if both args are bool. */
static PyObject *
bool_and(PyObject *a, PyObject *b)
{
if (!PyBool_Check(a) || !PyBool_Check(b))
return PyInt_Type.tp_as_number->nb_and(a, b);
return PyBool_FromLong(
((PyBoolObject *)a)->ob_ival & ((PyBoolObject *)b)->ob_ival);
}
static PyObject *
bool_or(PyObject *a, PyObject *b)
{
if (!PyBool_Check(a) || !PyBool_Check(b))
return PyInt_Type.tp_as_number->nb_or(a, b);
return PyBool_FromLong(
((PyBoolObject *)a)->ob_ival | ((PyBoolObject *)b)->ob_ival);
}
static PyObject *
bool_xor(PyObject *a, PyObject *b)
{
if (!PyBool_Check(a) || !PyBool_Check(b))
return PyInt_Type.tp_as_number->nb_xor(a, b);
return PyBool_FromLong(
((PyBoolObject *)a)->ob_ival ^ ((PyBoolObject *)b)->ob_ival);
}
/* Doc string */
PyDoc_STRVAR(bool_doc,
"bool(x) -> bool\n\
\n\
Returns True when the argument x is true, False otherwise.\n\
The builtins True and False are the only two instances of the class bool.\n\
The class bool is a subclass of the class int, and cannot be subclassed.");
/* Arithmetic methods -- only so we can override &, |, ^. */
static PyNumberMethods bool_as_number = {
0, /* nb_add */
0, /* nb_subtract */
0, /* nb_multiply */
0, /* nb_divide */
0, /* nb_remainder */
0, /* nb_divmod */
0, /* nb_power */
0, /* nb_negative */
0, /* nb_positive */
0, /* nb_absolute */
0, /* nb_nonzero */
0, /* nb_invert */
0, /* nb_lshift */
0, /* nb_rshift */
bool_and, /* nb_and */
bool_xor, /* nb_xor */
bool_or, /* nb_or */
0, /* nb_coerce */
0, /* nb_int */
0, /* nb_long */
0, /* nb_float */
0, /* nb_oct */
0, /* nb_hex */
0, /* nb_inplace_add */
0, /* nb_inplace_subtract */
0, /* nb_inplace_multiply */
0, /* nb_inplace_divide */
0, /* nb_inplace_remainder */
0, /* nb_inplace_power */
0, /* nb_inplace_lshift */
0, /* nb_inplace_rshift */
0, /* nb_inplace_and */
0, /* nb_inplace_xor */
0, /* nb_inplace_or */
0, /* nb_floor_divide */
0, /* nb_true_divide */
0, /* nb_inplace_floor_divide */
0, /* nb_inplace_true_divide */
};
/* The type object for bool. Note that this cannot be subclassed! */
PyTypeObject PyBool_Type = {
PyObject_HEAD_INIT(&PyType_Type)
0,
"bool",
sizeof(PyIntObject),
0,
0, /* tp_dealloc */
(printfunc)bool_print, /* tp_print */
0, /* tp_getattr */
0, /* tp_setattr */
0, /* tp_compare */
(reprfunc)bool_repr, /* tp_repr */
&bool_as_number, /* tp_as_number */
0, /* tp_as_sequence */
0, /* tp_as_mapping */
0, /* tp_hash */
0, /* tp_call */
(reprfunc)bool_repr, /* tp_str */
0, /* tp_getattro */
0, /* tp_setattro */
0, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_CHECKTYPES, /* tp_flags */
bool_doc, /* tp_doc */
0, /* tp_traverse */
0, /* tp_clear */
0, /* tp_richcompare */
0, /* tp_weaklistoffset */
0, /* tp_iter */
0, /* tp_iternext */
0, /* tp_methods */
0, /* tp_members */
0, /* tp_getset */
&PyInt_Type, /* tp_base */
0, /* tp_dict */
0, /* tp_descr_get */
0, /* tp_descr_set */
0, /* tp_dictoffset */
0, /* tp_init */
0, /* tp_alloc */
bool_new, /* tp_new */
};
/* The objects representing bool values False and True */
/* Named Zero for link-level compatibility */
PyIntObject _Py_ZeroStruct = {
PyObject_HEAD_INIT(&PyBool_Type)
0
};
PyIntObject _Py_TrueStruct = {
PyObject_HEAD_INIT(&PyBool_Type)
1
};