[Python-Dev] strptime recapped

[Brett Cannon]

I have written the callout to strptime.strptime (strptime is SF patch
#474274) as Guido asked.  Since that was the current hold-up and the
thread has gone dormant, I figured I should summarize the discussion up to
this point.

1) what is the need?:
The question was raised why this was done.  The answer was that since time
is just a wrapper around time.h, strptime was not guaranteed since it is
not a part of ANSI C.  Some ANSI C libraries include it, though (like
glibc), because it is so useful.  Unfortunately Windows and OS X do not
have it.  Having it in Python means it is completely portable and no
longer reliant on the ANSI C library being kind enough to provide it.

2) strftime dependence:
Some people worried about the dependence upon strftime for calculating
some info.  But since strftime is guaranteed to be there by Python (since
it is a part of ANSI C), the dependence is not an issue.

3) locale info for dates:
Skip and Guido pointed out that calendar.py now generates the names of
the weekdays and months on the fly similar to my solution.  So I did go
ahead and use it.  But Skip pointed out that perhaps we should centralize
any code that calculates locale info for dates (calendar.py's names and my
code for figuring out format for date/time).  I had suggested adding it to
the locale module and Guido responded that Martin had to ok that.  Martin
hasn't responded to that idea.

4) location of strptime:
Skip asked why Guido was having me write the callout patch to
timemodule.c.  He wondered why Lib/time.py wasn't just created holding my
code and then renaming timemodule.c to _timemodule.c and importing it at
the end of time.py.  No response has been given thus far for that.

I also suggested a possible time2 where things like strptime, my helper
fxns (calculate the Julian date from the Gregorian date, etc.), and things
such as naivetime could be kept.  That would allow time to stay as a
straight wrapper to time.h while all bonus code gets relegated to time2.
Guido said it might be a good idea but would have to wait until he got
back from vacation.


That pretty much sums up everything to this point; hope I got it right and
didn't miss anything.

-Brett C.