diff options
Diffstat (limited to 'Doc/whatsnew')
| -rw-r--r-- | Doc/whatsnew/3.1.rst | 84 |
1 files changed, 50 insertions, 34 deletions
diff --git a/Doc/whatsnew/3.1.rst b/Doc/whatsnew/3.1.rst index 76f0b26..b38ad8a 100644 --- a/Doc/whatsnew/3.1.rst +++ b/Doc/whatsnew/3.1.rst @@ -82,12 +82,12 @@ the original insertion position is left unchanged. Deleting an entry and reinserting it will move it to the end. The standard library now supports use of ordered dictionaries in several -modules. The :mod:`ConfigParser` modules uses them by default. This lets +modules. The :mod:`ConfigParser` module uses them by default. This lets configuration files be read, modified, and then written back in their original order. The :mod:`collections` module's :meth:`namedtuple._asdict` method now -returns a dictionary with the values appearing in the same order as the -underlying tuple.count The :mod:`json` module is being built-out with an -*object_pairs_hook* to allow OrderedDicts to be built by the decoder. +returns an ordered dictionary with the values appearing in the same order as +the underlying tuple indicies. The :mod:`json` module is being built-out with +an *object_pairs_hook* to allow OrderedDicts to be built by the decoder. Support was also added for third-party tools like PyYAML. .. seealso:: @@ -107,10 +107,12 @@ program's output, improving its professional appearance and readability:: >>> format(Decimal('1234567.89'), ',f') '1,234,567.89' -The currently supported types are :class:`int` and :class:`Decimal`. +The currently supported types are :class:`int` and :class:`decimal.Decimal`. Support for :class:`float` is expected before the beta release. Discussions are underway about how to specify alternative separators -like dots, spaces, apostrophes, or underscores. +like dots, spaces, apostrophes, or underscores. Locale-aware applications +should use the existing *n* format specifier which already has some support +for thousands separators. .. seealso:: @@ -138,30 +140,8 @@ Some smaller changes made to the core Python language are: >>> (n+1).bit_length() 124 - (Contributed by Fredrik Johansson and Victor Stinner; :issue:`3439`.) - -* Integers are now stored internally either in base 2**15 or in base - 2**30, the base being determined at build time. Previously, they - were always stored in base 2**15. Using base 2**30 gives - significant performance improvements on 64-bit machines, but - benchmark results on 32-bit machines have been mixed. Therefore, - the default is to use base 2**30 on 64-bit machines and base 2**15 - on 32-bit machines; on Unix, there's a new configure option - --enable-big-digits that can be used to override this default. - - Apart from the performance improvements this change should be - invisible to end users, with one exception: for testing and - debugging purposes there's a new structseq ``sys.int_info`` that - provides information about the internal format, giving the number of - bits per digit and the size in bytes of the C type used to store - each digit:: - - >>> import sys - >>> sys.int_info - sys.int_info(bits_per_digit=30, sizeof_digit=4) - - (Contributed by Mark Dickinson; :issue:`4258`.) - + (Contributed by Fredrik Johansson, Victor Stinner, Raymond Hettinger, + and Mark Dickinson; :issue:`3439`.) * Added a :class:`collections.Counter` class to support convenient counting of unique items in a sequence or iterable:: @@ -224,7 +204,7 @@ Some smaller changes made to the core Python language are: (Contributed by Raymond Hettinger; :issue:`1818`.) -* :func:`round`(x, n) now returns an integer if *x* is an integer. +* ``round`(x, n)`` now returns an integer if *x* is an integer. Previously it returned a float. (Contributed by Mark Dickinson; :issue:`4707`.) @@ -250,9 +230,20 @@ Some smaller changes made to the core Python language are: (Suggested by Antoine Pitrou and Jesse Noller. Implemented by Jack Diedrich; :issue:`5228`.) -XXX Brett Cannon's importlib package +* The :mod:`unittest` module now supports skipping individual tests or classes + of tests. And it supports marking a test as a expected failure, a test that + is known to be broken, but shouldn’t be counted as a failure on a + TestResult. + + (Contributed by Benjamin Peterson.) -XXX New unittest assert methods +* A new module, :mod:`importlib` was added. It provides a complete, portable, + pure Python reference implementation of the *import* statement and its + counterpart, the :func:`import__` function. It represents a substantial + step forward in documenting and defining the actions that take place during + imports. + + (Contributed by Brett Cannon.) .. ====================================================================== @@ -297,6 +288,31 @@ Major performance enhancements have been added: (Contributed by Antoine Pitrou and Amaury Forgeot d'Arc, :issue:`4868`.) -XXX The JSON module is getting a C extension for speed. +* The :mod:`json` module is getting a C extension to substantially improve + its performance. The code is expected to be added in-time for the beta + release. + + (Contributed by Bob Ippolito.) + +* Integers are now stored internally either in base 2**15 or in base + 2**30, the base being determined at build time. Previously, they + were always stored in base 2**15. Using base 2**30 gives + significant performance improvements on 64-bit machines, but + benchmark results on 32-bit machines have been mixed. Therefore, + the default is to use base 2**30 on 64-bit machines and base 2**15 + on 32-bit machines; on Unix, there's a new configure option + ``--enable-big-digits`` that can be used to override this default. + + Apart from the performance improvements this change should be invisible to + end users, with one exception: for testing and debugging purposes there's a + new :class:`structseq` ``sys.int_info`` that provides information about the + internal format, giving the number of bits per digit and the size in bytes + of the C type used to store each digit:: + + >>> import sys + >>> sys.int_info + sys.int_info(bits_per_digit=30, sizeof_digit=4) + + (Contributed by Mark Dickinson; :issue:`4258`.) .. ====================================================================== |