From 8858d2cb84c30908302c533ba92a3c42dabefe04 Mon Sep 17 00:00:00 2001 From: Mark Dickinson Date: Sun, 15 Aug 2010 09:43:29 +0000 Subject: [PATCH] Clarify whatsnew entry for short float repr: roundtripping is not a new feature in 2.7. --- Doc/whatsnew/2.7.rst | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/Doc/whatsnew/2.7.rst b/Doc/whatsnew/2.7.rst index 5aa632a5610..b2725c93887 100644 --- a/Doc/whatsnew/2.7.rst +++ b/Doc/whatsnew/2.7.rst @@ -143,10 +143,12 @@ A partial list of 3.1 features that were backported to 2.7: * The :class:`memoryview` object. * A small subset of the :mod:`importlib` module, `described below <#importlib-section>`__. -* Float-to-string and string-to-float conversions now round their - results more correctly, and :func:`repr` of a floating-point - number *x* returns a result that's guaranteed to round back to the - same number when converted back to a float. +* The :func:`repr` of a float ``x`` is shorter in many cases: it's now + based on the shortest decimal string that's guaranteed to round back + to ``x``. As in previous versions of Python, it's guaranteed that + ``float(repr(x))`` recovers ``x``. +* Float-to-string and string-to-float conversions are correctly rounded. + The :func:`round` function is also now correctly rounded. * The :ctype:`PyCapsule` type, used to provide a C API for extension modules. * The :cfunc:`PyLong_AsLongAndOverflow` C API function.