[Python-Dev] Proposal: make float.__str__ identical to float__repr__ in Python 3.2

Mark Dickinson dickinsm at gmail.com
Thu Jul 29 20:47:37 CEST 2010

Now that we've got the short float repr in Python, there's less value
in having float.__str__ truncate to 12 significant digits (as it
currently does).  For Python 3.2, I propose making float.__str__ use
the same algorithm as float.__repr__ for its output (and similarly for

Apart from simplifying the internals a little bit, one nice feature of
this change is that it removes the differences in formatting between
printing a float and printing a container of floats:

>>> l = [1/3, 1/5, 1/7]
>>> print(l)
[0.3333333333333333, 0.2, 0.14285714285714285]
>>> print(l[0], l[1], l[2])
0.333333333333 0.2 0.142857142857

Any thoughts or comments on this?

There's a working patch at http://bugs.python.org/issue9337


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