Alexander Belopolsky <belopol...@users.sourceforge.net> added the comment:

After reading the new wording on a formatted page, I don't like the proposed 
changes:

"""
time.altzone

When daylight is nonzero, altzone specifies the offset of the local DST 
timezone, in seconds west of UTC. This is negative if the local DST timezone is 
east of UTC ...
"""

In the second sentence, it is not clear whether "this" refers to altzone or 
daylight.

"""
time.daylight

Whether or not DST is in effect, daylight specifies the DST offset. 
"""

This is simply wrong.  time.daylight does not necessarily specify the DST 
offset (and I think it does not on most systems.)  POSIX requires that "The 
tzset() function also shall set the external variable daylight to 0 if Daylight 
Savings Time conversions should never be applied for the timezone in use; 
otherwise, non-zero." [1]  This means that a compliant system may store just 0 
or 1 in daylight rather than the DST offset.

For example, on my OSX system:

$ TZ=America/New_York python -c "import time; print(time.daylight)"
1
$ TZ=UTC python -c "import time; print(time.daylight)"
0
$ TZ=EDT python -c "import time; print(time.daylight)"
0

I will think some more on how to improve the current documentation, but at 
least with respect to time.daylight, current language is better than the 
proposed change.




[1] http://www.opengroup.org/onlinepubs/009695399/functions/tzset.html

----------
superseder:  -> Don't use east/west of UTC in date/time documentation

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