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Closes #27207: Merge with 3.5

This commit is contained in:
Zachary Ware 2016-08-10 00:31:31 -05:00
parent c17dd50957 4032620f93
commit 75bc032341
1 changed files with 31 additions and 18 deletions
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Doc/whatsnew/3.2.rst
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@ -313,14 +313,14 @@ aspects that are visible to the programmer:
of the actual file that was imported:
>>> import collections
>>> collections.__cached__
>>> collections.__cached__ # doctest: +SKIP
'c:/py32/lib/__pycache__/collections.cpython-32.pyc'
* The tag that is unique to each interpreter is accessible from the :mod:`imp`
module:
>>> import imp
>>> imp.get_tag()
>>> imp.get_tag() # doctest: +SKIP
'cpython-32'
* Scripts that try to deduce source filename from the imported file now need to
@ -329,7 +329,7 @@ aspects that are visible to the programmer:
>>> imp.source_from_cache('c:/py32/lib/__pycache__/collections.cpython-32.pyc')
'c:/py32/lib/collections.py'
>>> imp.cache_from_source('c:/py32/lib/collections.py')
>>> imp.cache_from_source('c:/py32/lib/collections.py') # doctest: +SKIP
'c:/py32/lib/__pycache__/collections.cpython-32.pyc'
* The :mod:`py_compile` and :mod:`compileall` modules have been updated to
@ -532,7 +532,7 @@ Some smaller changes made to the core Python language are:
original object.
>>> with memoryview(b'abcdefgh') as v:
print(v.tolist())
... print(v.tolist())
[97, 98, 99, 100, 101, 102, 103, 104]
(Added by Antoine Pitrou; :issue:`9757`.)
@ -568,9 +568,10 @@ Some smaller changes made to the core Python language are:
expect a tuple as an argument. This is a big step forward in making the C
structures as flexible as their pure Python counterparts:
>>> import sys
>>> isinstance(sys.version_info, tuple)
True
>>> 'Version %d.%d.%d %s(%d)' % sys.version_info
>>> 'Version %d.%d.%d %s(%d)' % sys.version_info # doctest: +SKIP
'Version 3.2.0 final(0)'
(Suggested by Arfrever Frehtes Taifersar Arahesis and implemented
@ -757,18 +758,18 @@ functools
>>> import functools
>>> @functools.lru_cache(maxsize=300)
>>> def get_phone_number(name):
c = conn.cursor()
c.execute('SELECT phonenumber FROM phonelist WHERE name=?', (name,))
return c.fetchone()[0]
... def get_phone_number(name):
... c = conn.cursor()
... c.execute('SELECT phonenumber FROM phonelist WHERE name=?', (name,))
... return c.fetchone()[0]
>>> for name in user_requests:
get_phone_number(name) # cached lookup
>>> for name in user_requests: # doctest: +SKIP
... get_phone_number(name) # cached lookup
To help with choosing an effective cache size, the wrapped function is
instrumented for tracking cache statistics:
>>> get_phone_number.cache_info()
>>> get_phone_number.cache_info() # doctest: +SKIP
CacheInfo(hits=4805, misses=980, maxsize=300, currsize=300)
If the phonelist table gets updated, the outdated contents of the cache can be
@ -823,7 +824,7 @@ functools
modern :term:`key function`:
>>> # locale-aware sort order
>>> sorted(iterable, key=cmp_to_key(locale.strcoll))
>>> sorted(iterable, key=cmp_to_key(locale.strcoll)) # doctest: +SKIP
For sorting examples and a brief sorting tutorial, see the `Sorting HowTo
<https://wiki.python.org/moin/HowTo/Sorting/>`_ tutorial.
@ -861,7 +862,8 @@ collections
which only have positive counts, and the latter is more suitable for use cases
that allow negative counts:
>>> tally = Counter(dogs=5, cat=3)
>>> from collections import Counter
>>> tally = Counter(dogs=5, cats=3)
>>> tally -= Counter(dogs=2, cats=8) # saturating subtraction
>>> tally
Counter({'dogs': 3})
@ -884,6 +886,7 @@ collections
an ordered dictionary can be used to track order of access by aging entries
from the oldest to the most recently accessed.
>>> from collections import OrderedDict
>>> d = OrderedDict.fromkeys(['a', 'b', 'X', 'd', 'e'])
>>> list(d)
['a', 'b', 'X', 'd', 'e']
@ -897,6 +900,7 @@ collections
:meth:`~collections.deque.count` and :meth:`~collections.deque.reverse` that
make them more substitutable for :class:`list` objects:
>>> from collections import deque
>>> d = deque('simsalabim')
>>> d.count('s')
2
@ -1042,6 +1046,7 @@ The :func:`~math.isfinite` function provides a reliable and fast way to detect
special values. It returns *True* for regular numbers and *False* for *Nan* or
*Infinity*:
>>> from math import isfinite
>>> [isfinite(x) for x in (123, 4.56, float('Nan'), float('Inf'))]
[True, True, False, False]
@ -1049,6 +1054,7 @@ The :func:`~math.expm1` function computes ``e**x-1`` for small values of *x*
without incurring the loss of precision that usually accompanies the subtraction
of nearly equal quantities:
>>> from math import expm1
>>> expm1(0.013671875) # more accurate way to compute e**x-1 for a small x
0.013765762467652909
@ -1056,6 +1062,7 @@ The :func:`~math.erf` function computes a probability integral or `Gaussian
error function <https://en.wikipedia.org/wiki/Error_function>`_. The
complementary error function, :func:`~math.erfc`, is ``1 - erf(x)``:
>>> from math import erf, erfc, sqrt
>>> erf(1.0/sqrt(2.0)) # portion of normal distribution within 1 standard deviation
0.682689492137086
>>> erfc(1.0/sqrt(2.0)) # portion of normal distribution outside 1 standard deviation
@ -1069,6 +1076,7 @@ the function is related to factorials, it grows large even for small values of
*x*, so there is also a :func:`~math.lgamma` function for computing the natural
logarithm of the gamma function:
>>> from math import gamma, lgamma
>>> gamma(7.0) # six factorial
720.0
>>> lgamma(801.0) # log(800 factorial)
@ -1287,7 +1295,7 @@ Some of the hashing details are exposed through a new attribute,
prime modulus, the hash values for *infinity* and *nan*, and the multiplier
used for the imaginary part of a number:
>>> sys.hash_info
>>> sys.hash_info # doctest: +SKIP
sys.hash_info(width=64, modulus=2305843009213693951, inf=314159, nan=0, imag=1000003)
An early decision to limit the inter-operability of various numeric types has
@ -1310,6 +1318,8 @@ Similar changes were made to :class:`fractions.Fraction` so that the
:meth:`~fractions.Fraction.from_float()` and :meth:`~fractions.Fraction.from_decimal`
methods are no longer needed (:issue:`8294`):
>>> from decimal import Decimal
>>> from fractions import Fraction
>>> Decimal(1.1)
Decimal('1.100000000000000088817841970012523233890533447265625')
>>> Fraction(1.1)
@ -1392,6 +1402,7 @@ The :mod:`gzip` module also gains the :func:`~gzip.compress` and
decompression. Keep in mind that text needs to be encoded as :class:`bytes`
before compressing and decompressing:
>>> import gzip
>>> s = 'Three shall be the number thou shalt count, '
>>> s += 'and the number of the counting shall be three'
>>> b = s.encode() # convert to utf-8
@ -1401,7 +1412,7 @@ before compressing and decompressing:
>>> len(c)
77
>>> gzip.decompress(c).decode()[:42] # decompress and convert to text
'Three shall be the number thou shalt count,'
'Three shall be the number thou shalt count'
(Contributed by Anand B. Pillai in :issue:`3488`; and by Antoine Pitrou, Nir
Aides and Brian Curtin in :issue:`9962`, :issue:`1675951`, :issue:`7471` and
@ -1503,6 +1514,7 @@ variables. The :mod:`os` module provides two new functions,
:func:`~os.fsencode` and :func:`~os.fsdecode`, for encoding and decoding
filenames:
>>> import os
>>> filename = 'Sehenswürdigkeiten'
>>> os.fsencode(filename)
b'Sehensw\xc3\xbcrdigkeiten'
@ -1740,6 +1752,7 @@ names.
:class:`unittest.case.TestCase` class can now be instantiated without
arguments:
>>> from unittest import TestCase
>>> TestCase().assertEqual(pow(2, 3), 8)
(Contributed by Michael Foord.)
@ -2201,7 +2214,7 @@ The :func:`~urllib.parse.urlparse` function now supports `IPv6
<https://en.wikipedia.org/wiki/IPv6>`_ addresses as described in :rfc:`2732`:
>>> import urllib.parse
>>> urllib.parse.urlparse('http://[dead:beef:cafe:5417:affe:8FA3:deaf:feed]/foo/')
>>> urllib.parse.urlparse('http://[dead:beef:cafe:5417:affe:8FA3:deaf:feed]/foo/') # doctest: +NORMALIZE_WHITESPACE
ParseResult(scheme='http',
netloc='[dead:beef:cafe:5417:affe:8FA3:deaf:feed]',
path='/foo/',
@ -2235,7 +2248,7 @@ functions now accept ASCII-encoded byte strings as input, so long as they are
not mixed with regular strings. If ASCII-encoded byte strings are given as
parameters, the return types will also be an ASCII-encoded byte strings:
>>> urllib.parse.urlparse(b'http://www.python.org:80/about/')
>>> urllib.parse.urlparse(b'http://www.python.org:80/about/') # doctest: +NORMALIZE_WHITESPACE
ParseResultBytes(scheme=b'http', netloc=b'www.python.org:80',
path=b'/about/', params=b'', query=b'', fragment=b'')