Index: Objects/intobject.c
===================================================================
--- Objects/intobject.c	(révision 67186)
+++ Objects/intobject.c	(copie de travail)
@@ -1138,6 +1138,27 @@
 	return NULL;
 }
 
+static PyObject *
+int_numbits(PyIntObject *v)
+{
+	unsigned long n;
+	long result = 0;
+
+	if (v->ob_ival < 0) {
+		/* if LONG_MIN == -LONG_MAX-1 (true on most platforms) then
+		   ANSI C says that the result of -ival is undefined when ival
+		   == LONG_MIN.  Hence the following workaround. */
+		n = (unsigned long)(-1 - v->ob_ival) + 1;
+	} else {
+		n = (unsigned long)v->ob_ival;
+	}
+	while (n) {
+		++result;
+		n >>= 1;
+	}
+	return PyInt_FromLong(result);
+}
+
 #if 0
 static PyObject *
 int_is_finite(PyObject *v)
@@ -1147,6 +1168,8 @@
 #endif
 
 static PyMethodDef int_methods[] = {
+	{"numbits",	(PyCFunction)int_numbits, METH_NOARGS,
+	 "Returns the number of binary digits in self."},
 	{"conjugate",	(PyCFunction)int_int,	METH_NOARGS,
 	 "Returns self, the complex conjugate of any int."},
 #if 0
Index: Objects/longobject.c
===================================================================
--- Objects/longobject.c	(révision 67186)
+++ Objects/longobject.c	(copie de travail)
@@ -3451,6 +3451,58 @@
 	return PyInt_FromSsize_t(res);
 }
 
+static PyObject *
+long_numbits(PyLongObject *v)
+{
+	PyLongObject *result, *x, *y;
+	Py_ssize_t ndigits, msd_bits;
+	digit msd;
+
+	assert(v != NULL);
+	assert(PyLong_Check(v));
+	ndigits = ABS(Py_SIZE(v));
+	assert(ndigits == 0 || v->ob_digit[ndigits - 1] != 0);
+
+	if (ndigits == 0)
+		return PyLong_FromLong(0);
+
+	msd = v->ob_digit[ndigits - 1];
+	msd_bits = 0;
+	do {
+		++msd_bits;
+		msd >>= 1;
+	} while (msd);
+
+	result = (PyLongObject *)PyLong_FromLong(ndigits - 1);
+	if (!result)
+		return NULL;
+	x = (PyLongObject *)PyLong_FromLong(PyLong_SHIFT);
+	if (!x)
+		goto error;
+	y = (PyLongObject *)long_mul(result, x);
+	Py_DECREF(x);
+	if (!y)
+		goto error;
+	Py_DECREF(result);
+	result = y;
+
+	x = (PyLongObject *)PyLong_FromLong(msd_bits);
+	if (!x)
+		goto error;
+	y = (PyLongObject *)long_add(result, x);
+	Py_DECREF(x);
+	if (!y)
+		goto error;
+	Py_DECREF(result);
+	result = y;
+
+	return (PyObject *)result;
+
+error:
+	Py_DECREF(result);
+	return NULL;
+}
+
 #if 0
 static PyObject *
 long_is_finite(PyObject *v)
@@ -3460,6 +3512,8 @@
 #endif
 
 static PyMethodDef long_methods[] = {
+	{"numbits",	(PyCFunction)long_numbits, METH_NOARGS,
+	 "Returns the number of binary digits in self."},
 	{"conjugate",	(PyCFunction)long_long,	METH_NOARGS,
 	 "Returns self, the complex conjugate of any long."},
 #if 0
@@ -3476,6 +3530,10 @@
 };
 
 static PyGetSetDef long_getset[] = {
+/*    {"numbits",
+     (getter)PyLong_NumBits, (setter)NULL,
+     "number of bits in an integer",
+     NULL}, */
     {"real", 
      (getter)long_long, (setter)NULL,
      "the real part of a complex number",
Index: Doc/library/stdtypes.rst
===================================================================
--- Doc/library/stdtypes.rst	(révision 67186)
+++ Doc/library/stdtypes.rst	(copie de travail)
@@ -303,6 +303,9 @@
 +--------------------+---------------------------------+--------+
 | ``float(x)``       | *x* converted to floating point | \(6)   |
 +--------------------+---------------------------------+--------+
+| ``x.numbits()``    | number of bits of the absolute  |        |
+|                    | value of the integer *x*.       |        |
++--------------------+---------------------------------+--------+
 | ``complex(re,im)`` | a complex number with real part |        |
 |                    | *re*, imaginary part *im*.      |        |
 |                    | *im* defaults to zero.          |        |
Index: Lib/test/test_int.py
===================================================================
--- Lib/test/test_int.py	(révision 67186)
+++ Lib/test/test_int.py	(copie de travail)
@@ -240,6 +240,21 @@
         self.assertEqual(int('2br45qc', 35), 4294967297L)
         self.assertEqual(int('1z141z5', 36), 4294967297L)
 
+    def test_numbits(self):
+        self.assertEqual((0).numbits(), 0)
+        self.assertEqual((1).numbits(), 1)
+        self.assertEqual((-1).numbits(), 1)
+        self.assertEqual((2).numbits(), 2)
+        self.assertEqual((-2).numbits(), 2)
+        for i in [2, 3, 15, 16, 17, 31, 32, 33, 63, 64]:
+            a = 2**i
+            self.assertEqual((a-1).numbits(), i)
+            self.assertEqual((1-a).numbits(), i)
+            self.assertEqual((a).numbits(), i+1)
+            self.assertEqual((-a).numbits(), i+1)
+            self.assertEqual((a+1).numbits(), i+1)
+            self.assertEqual((-a-1).numbits(), i+1)
+
     def test_intconversion(self):
         # Test __int__()
         class ClassicMissingMethods:
Index: Lib/test/test_long.py
===================================================================
--- Lib/test/test_long.py	(révision 67186)
+++ Lib/test/test_long.py	(copie de travail)
@@ -752,6 +752,22 @@
         self.assertRaises(OverflowError, long, float('-inf'))
         self.assertRaises(ValueError, long, float('nan'))
 
+    def test_numbits(self):
+        self.assertEqual((0L).numbits(), 0)
+        self.assertEqual((1L).numbits(), 1)
+        self.assertEqual((-1L).numbits(), 1)
+        self.assertEqual((2L).numbits(), 2)
+        self.assertEqual((-2L).numbits(), 2)
+        for i in [2, 3, 15, 16, 17, 31, 32, 33, 63, 64, 234]:
+            a = 2L**i
+            self.assertEqual((a-1).numbits(), i)
+            self.assertEqual((1-a).numbits(), i)
+            self.assertEqual((a).numbits(), i+1)
+            self.assertEqual((-a).numbits(), i+1)
+            self.assertEqual((a+1).numbits(), i+1)
+            self.assertEqual((-a-1).numbits(), i+1)
+
+
 def test_main():
     test_support.run_unittest(LongTest)