1 /* Boolean type, a subtype of int */
2
3 #include "Python.h"
4 #include "longintrepr.h"
5
6 /* We define bool_repr to return "False" or "True" */
7
8 static PyObject *false_str = NULL;
9 static PyObject *true_str = NULL;
10
11 static PyObject *
bool_repr(PyObject * self)12 bool_repr(PyObject *self)
13 {
14 PyObject *s;
15
16 if (self == Py_True)
17 s = true_str ? true_str :
18 (true_str = PyUnicode_InternFromString("True"));
19 else
20 s = false_str ? false_str :
21 (false_str = PyUnicode_InternFromString("False"));
22 Py_XINCREF(s);
23 return s;
24 }
25
26 /* Function to return a bool from a C long */
27
PyBool_FromLong(long ok)28 PyObject *PyBool_FromLong(long ok)
29 {
30 PyObject *result;
31
32 if (ok)
33 result = Py_True;
34 else
35 result = Py_False;
36 Py_INCREF(result);
37 return result;
38 }
39
40 /* We define bool_new to always return either Py_True or Py_False */
41
42 static PyObject *
bool_new(PyTypeObject * type,PyObject * args,PyObject * kwds)43 bool_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
44 {
45 PyObject *x = Py_False;
46 long ok;
47
48 if (!_PyArg_NoKeywords("bool", kwds))
49 return NULL;
50 if (!PyArg_UnpackTuple(args, "bool", 0, 1, &x))
51 return NULL;
52 ok = PyObject_IsTrue(x);
53 if (ok < 0)
54 return NULL;
55 return PyBool_FromLong(ok);
56 }
57
58 /* Arithmetic operations redefined to return bool if both args are bool. */
59
60 static PyObject *
bool_and(PyObject * a,PyObject * b)61 bool_and(PyObject *a, PyObject *b)
62 {
63 if (!PyBool_Check(a) || !PyBool_Check(b))
64 return PyLong_Type.tp_as_number->nb_and(a, b);
65 return PyBool_FromLong((a == Py_True) & (b == Py_True));
66 }
67
68 static PyObject *
bool_or(PyObject * a,PyObject * b)69 bool_or(PyObject *a, PyObject *b)
70 {
71 if (!PyBool_Check(a) || !PyBool_Check(b))
72 return PyLong_Type.tp_as_number->nb_or(a, b);
73 return PyBool_FromLong((a == Py_True) | (b == Py_True));
74 }
75
76 static PyObject *
bool_xor(PyObject * a,PyObject * b)77 bool_xor(PyObject *a, PyObject *b)
78 {
79 if (!PyBool_Check(a) || !PyBool_Check(b))
80 return PyLong_Type.tp_as_number->nb_xor(a, b);
81 return PyBool_FromLong((a == Py_True) ^ (b == Py_True));
82 }
83
84 /* Doc string */
85
86 PyDoc_STRVAR(bool_doc,
87 "bool(x) -> bool\n\
88 \n\
89 Returns True when the argument x is true, False otherwise.\n\
90 The builtins True and False are the only two instances of the class bool.\n\
91 The class bool is a subclass of the class int, and cannot be subclassed.");
92
93 /* Arithmetic methods -- only so we can override &, |, ^. */
94
95 static PyNumberMethods bool_as_number = {
96 0, /* nb_add */
97 0, /* nb_subtract */
98 0, /* nb_multiply */
99 0, /* nb_remainder */
100 0, /* nb_divmod */
101 0, /* nb_power */
102 0, /* nb_negative */
103 0, /* nb_positive */
104 0, /* nb_absolute */
105 0, /* nb_bool */
106 0, /* nb_invert */
107 0, /* nb_lshift */
108 0, /* nb_rshift */
109 bool_and, /* nb_and */
110 bool_xor, /* nb_xor */
111 bool_or, /* nb_or */
112 0, /* nb_int */
113 0, /* nb_reserved */
114 0, /* nb_float */
115 0, /* nb_inplace_add */
116 0, /* nb_inplace_subtract */
117 0, /* nb_inplace_multiply */
118 0, /* nb_inplace_remainder */
119 0, /* nb_inplace_power */
120 0, /* nb_inplace_lshift */
121 0, /* nb_inplace_rshift */
122 0, /* nb_inplace_and */
123 0, /* nb_inplace_xor */
124 0, /* nb_inplace_or */
125 0, /* nb_floor_divide */
126 0, /* nb_true_divide */
127 0, /* nb_inplace_floor_divide */
128 0, /* nb_inplace_true_divide */
129 0, /* nb_index */
130 };
131
132 /* The type object for bool. Note that this cannot be subclassed! */
133
134 PyTypeObject PyBool_Type = {
135 PyVarObject_HEAD_INIT(&PyType_Type, 0)
136 "bool",
137 sizeof(struct _longobject),
138 0,
139 0, /* tp_dealloc */
140 0, /* tp_vectorcall_offset */
141 0, /* tp_getattr */
142 0, /* tp_setattr */
143 0, /* tp_as_async */
144 bool_repr, /* tp_repr */
145 &bool_as_number, /* tp_as_number */
146 0, /* tp_as_sequence */
147 0, /* tp_as_mapping */
148 0, /* tp_hash */
149 0, /* tp_call */
150 0, /* tp_str */
151 0, /* tp_getattro */
152 0, /* tp_setattro */
153 0, /* tp_as_buffer */
154 Py_TPFLAGS_DEFAULT, /* tp_flags */
155 bool_doc, /* tp_doc */
156 0, /* tp_traverse */
157 0, /* tp_clear */
158 0, /* tp_richcompare */
159 0, /* tp_weaklistoffset */
160 0, /* tp_iter */
161 0, /* tp_iternext */
162 0, /* tp_methods */
163 0, /* tp_members */
164 0, /* tp_getset */
165 &PyLong_Type, /* tp_base */
166 0, /* tp_dict */
167 0, /* tp_descr_get */
168 0, /* tp_descr_set */
169 0, /* tp_dictoffset */
170 0, /* tp_init */
171 0, /* tp_alloc */
172 bool_new, /* tp_new */
173 };
174
175 /* The objects representing bool values False and True */
176
177 struct _longobject _Py_FalseStruct = {
178 PyVarObject_HEAD_INIT(&PyBool_Type, 0)
179 { 0 }
180 };
181
182 struct _longobject _Py_TrueStruct = {
183 PyVarObject_HEAD_INIT(&PyBool_Type, 1)
184 { 1 }
185 };
186