1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
|
****************************
What's New In Python 3.5
****************************
:Release: |release|
:Date: |today|
.. Rules for maintenance:
* Anyone can add text to this document. Do not spend very much time
on the wording of your changes, because your text will probably
get rewritten to some degree.
* The maintainer will go through Misc/NEWS periodically and add
changes; it's therefore more important to add your changes to
Misc/NEWS than to this file.
* This is not a complete list of every single change; completeness
is the purpose of Misc/NEWS. Some changes I consider too small
or esoteric to include. If such a change is added to the text,
I'll just remove it. (This is another reason you shouldn't spend
too much time on writing your addition.)
* If you want to draw your new text to the attention of the
maintainer, add 'XXX' to the beginning of the paragraph or
section.
* It's OK to just add a fragmentary note about a change. For
example: "XXX Describe the transmogrify() function added to the
socket module." The maintainer will research the change and
write the necessary text.
* You can comment out your additions if you like, but it's not
necessary (especially when a final release is some months away).
* Credit the author of a patch or bugfix. Just the name is
sufficient; the e-mail address isn't necessary.
* It's helpful to add the bug/patch number as a comment:
XXX Describe the transmogrify() function added to the socket
module.
(Contributed by P.Y. Developer in :issue:`12345`.)
This saves the maintainer the effort of going through the Mercurial log
when researching a change.
This article explains the new features in Python 3.5, compared to 3.4.
For full details, see the :source:`Misc/NEWS` file.
.. note:: Prerelease users should be aware that this document is currently in
draft form. It will be updated substantially as Python 3.5 moves towards
release, so it's worth checking back even after reading earlier versions.
.. seealso::
.. :pep:`4XX` - Python 3.5 Release Schedule
Summary -- Release highlights
=============================
.. This section singles out the most important changes in Python 3.3.
Brevity is key.
New syntax features:
* None yet.
New library modules:
* None yet.
New built-in features:
* None yet.
Implementation improvements:
* When the ``LC_TYPE`` locale is the POSIX locale (``C`` locale),
:py:data:`sys.stdin` and :py:data:`sys.stdout` are now using the
``surrogateescape`` error handler, instead of the ``strict`` error handler
(:issue:`19977`).
Significantly Improved Library Modules:
* None yet.
Security improvements:
* None yet.
Please read on for a comprehensive list of user-facing changes.
.. PEP-sized items next.
.. _pep-4XX:
.. PEP 4XX: Virtual Environments
.. =============================
.. (Implemented by Foo Bar.)
.. .. seealso::
:pep:`4XX` - Python Virtual Environments
PEP written by Carl Meyer
Other Language Changes
======================
Some smaller changes made to the core Python language are:
* None yet.
New Modules
===========
.. module name
.. -----------
* None yet.
Improved Modules
================
doctest
-------
* :func:`doctest.DocTestSuite` returns an empty :class:`unittest.TestSuite` if
*module* contains no docstrings instead of raising :exc:`ValueError`
(contributed by Glenn Jones in :issue:`15916`).
importlib
---------
* :class:`importlib.util.LazyLoader` allows for the lazy loading of modules in
applications where startup time is paramount (contributed by Brett Cannon in
:issue:`17621`).
* :func:`importlib.abc.InspectLoader.source_to_code` is now a
static method to make it easier to work with source code in a string.
With a module object that you want to initialize you can then use
``exec(code, module.__dict__)`` to execute the code in the module.
inspect
-------
* :class:`inspect.Signature` and :class:`inspect.Parameter` are now
picklable and hashable (contributed by Yury Selivanov in :issue:`20726`
and :issue:`20334`).
* New class method :meth:`inspect.Signature.from_callable`, which makes
subclassing of :class:`~inspect.Signature` easier (contributed
by Yury Selivanov and Eric Snow in :issue:`17373`).
ipaddress
---------
* :class:`ipaddress.IPv4Network` and :class:`ipaddress.IPv6Network` now
accept an ``(address, netmask)`` tuple argument, so as to easily construct
network objects from existing addresses (contributed by Peter Moody
and Antoine Pitrou in :issue:`16531`).
signal
------
* Different constants of :mod:`signal` module are now enumeration values using
the :mod:`enum` module. This allows meaningful names to be printed during
debugging, instead of integer “magic numbers”. (contribute by Giampaolo
Rodola' in :issue:`21076`)
xmlrpc
------
* :class:`xmlrpc.client.ServerProxy` is now a :term:`context manager`
(contributed by Claudiu Popa in :issue:`20627`).
Optimizations
=============
The following performance enhancements have been added:
* Construction of ``bytes(int)`` and ``bytearray(int)`` (filled by zero bytes)
is faster and use less memory (until the bytearray buffer is filled with
data) for large objects. ``calloc()`` is used instead of ``malloc()`` to
allocate memory for these objects.
* Some operations on :class:`~ipaddress.IPv4Network` and
:class:`~ipaddress.IPv6Network` have been massively sped up, such as
:meth:`~ipaddress.IPv4Network.subnets`, :meth:`~ipaddress.IPv4Network.supernet`,
:func:`~ipaddress.summarize_address_range`, :func:`~ipaddress.collapse_addresses`.
The speed up can range from 3x to 15x.
(:issue:`21486`, :issue:`21487`, :issue:`20826`)
Build and C API Changes
=======================
Changes to Python's build process and to the C API include:
* New ``calloc`` functions:
* :c:func:`PyMem_RawCalloc`
* :c:func:`PyMem_Calloc`
* :c:func:`PyObject_Calloc`
* :c:func:`_PyObject_GC_Calloc`
Deprecated
==========
Unsupported Operating Systems
-----------------------------
* None yet.
Deprecated Python modules, functions and methods
------------------------------------------------
* The :mod:`formatter` module has now graduated to full deprecation and is still
slated for removal in Python 3.6.
Deprecated functions and types of the C API
-------------------------------------------
* None yet.
Deprecated features
-------------------
* None yet.
Porting to Python 3.5
=====================
This section lists previously described changes and other bugfixes
that may require changes to your code.
Changes in the Python API
-------------------------
* Before Python 3.5, a :class:`datetime.time` object was considered to be false
if it represented midnight in UTC. This behavior was considered obscure and
error-prone and has been removed in Python 3.5. See :issue:`13936` for full
details.
* :meth:`ssl.SSLSocket.send()` now raises either :exc:`ssl.SSLWantReadError`
or :exc:`ssl.SSLWantWriteError` on a non-blocking socket if the operation
would block. Previously, it would return 0. See :issue:`20951`.
Changes in the C API
--------------------
* The :c:type:`PyMemAllocator` structure has a new ``calloc`` field.
|
