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-rw-r--r--Doc/whatsnew/2.6.rst28
1 files changed, 23 insertions, 5 deletions
diff --git a/Doc/whatsnew/2.6.rst b/Doc/whatsnew/2.6.rst
index 9959ecd..c0ecf01 100644
--- a/Doc/whatsnew/2.6.rst
+++ b/Doc/whatsnew/2.6.rst
@@ -785,7 +785,7 @@ documentation for a :ref:`complete list <formatstrings>`; here's a sample::
'%' - Percentage. Multiplies the number by 100 and displays
in fixed ('f') format, followed by a percent sign.
-Classes and types can define a __format__ method to control how they're
+Classes and types can define a :meth:`__format__` method to control how they're
formatted. It receives a single argument, the format specifier::
def __format__(self, format_spec):
@@ -1515,10 +1515,22 @@ Here are all of the changes that Python 2.6 makes to the core Python language.
:func:`isnan`, return true if their floating-point argument is
infinite or Not A Number. (:issue:`1640`)
- The float type has a new instance method :meth:`float.hex` and a
- corresponding new class method :meth:`float.fromhex` to convert
- floating-point numbers to and from hexadecimal strings,
- respectively. (:issue:`3008`)
+ Conversion functions were added to convert floating-point numbers
+ into hexadecimal strings. (:issue:`3008`) These functions lets you
+ convert floats to and from a string representation without
+ introducing rounding errors from the conversion between decimal and
+ binary. Floats have a :meth:`hex` method that returns a string
+ representation, and the ``float.fromhex()`` method converts a string
+ back into a number::
+
+ >>> a = 3.75
+ >>> a.hex()
+ '0x1.e000000000000p+1'
+ >>> float.fromhex('0x1.e000000000000p+1')
+ 3.75
+ >>> b=1./3
+ >>> b.hex()
+ '0x1.5555555555555p-2'
* The :mod:`math` module has a number of new functions, and the existing
functions have been improved to give more consistent behaviour
@@ -1633,6 +1645,12 @@ Optimizations
(Original optimization implemented by Armin Rigo, updated for
Python 2.6 by Kevin Jacobs; :issue:`1700288`.)
+* Function calls that use keyword arguments
+ are significantly faster thanks to a patch that does a quick pointer
+ comparison, usually saving the time of a full string comparison.
+ (Contributed by Raymond Hettinger, after an initial implementation by
+ Antoine Pitrou; :issue:`1819`.)
+
* All of the functions in the :mod:`struct` module have been rewritten in
C, thanks to work at the Need For Speed sprint.
(Contributed by Raymond Hettinger.)