[Python-checkins] cpython (merge 3.5 -> default): merge 3.5

benjamin.peterson python-checkins at python.org
Fri May 27 01:57:07 EDT 2016


https://hg.python.org/cpython/rev/d63632b00b6e
changeset:   101517:d63632b00b6e
parent:      101514:09d6232e4705
parent:      101515:f4c5f63801c3
user:        Benjamin Peterson <benjamin at python.org>
date:        Thu May 26 22:56:51 2016 -0700
summary:
  merge 3.5

files:
  Doc/faq/programming.rst |  31 +----------------------------
  1 files changed, 1 insertions(+), 30 deletions(-)


diff --git a/Doc/faq/programming.rst b/Doc/faq/programming.rst
--- a/Doc/faq/programming.rst
+++ b/Doc/faq/programming.rst
@@ -1313,40 +1313,11 @@
 
 The technique, attributed to Randal Schwartz of the Perl community, sorts the
 elements of a list by a metric which maps each element to its "sort value". In
-Python, just use the ``key`` argument for the ``sort()`` method::
+Python, use the ``key`` argument for the :func:`sort()` function::
 
    Isorted = L[:]
    Isorted.sort(key=lambda s: int(s[10:15]))
 
-The ``key`` argument is new in Python 2.4, for older versions this kind of
-sorting is quite simple to do with list comprehensions.  To sort a list of
-strings by their uppercase values::
-
-  tmp1 = [(x.upper(), x) for x in L]  # Schwartzian transform
-  tmp1.sort()
-  Usorted = [x[1] for x in tmp1]
-
-To sort by the integer value of a subfield extending from positions 10-15 in
-each string::
-
-  tmp2 = [(int(s[10:15]), s) for s in L]  # Schwartzian transform
-  tmp2.sort()
-  Isorted = [x[1] for x in tmp2]
-
-For versions prior to 3.0, Isorted may also be computed by ::
-
-   def intfield(s):
-       return int(s[10:15])
-
-   def Icmp(s1, s2):
-       return cmp(intfield(s1), intfield(s2))
-
-   Isorted = L[:]
-   Isorted.sort(Icmp)
-
-but since this method calls ``intfield()`` many times for each element of L, it
-is slower than the Schwartzian Transform.
-
 
 How can I sort one list by values from another list?
 ----------------------------------------------------

-- 
Repository URL: https://hg.python.org/cpython


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