parsing a date

[Eric Abrahamsen <eric@ericabrahamsen.net>]

I'm reading in files with dates in this format: "2011-11-25". I need to
write them out as "2011/11/25". Instead of just manhandling the strings
(I'll likely need this date information in other places) I wanted to
parse the strings into proper date objects, then format them back into
strings. `date-to-time' doesn't work because (parse-time-string
"2011-11-15") gives me:

(nil nil nil 15 11 2011 nil nil nil)

Which is not acceptable to `encode-time', because it requires integers,
not nil. I can't believe this is quite this complicated: do I really
have to replace all the nils with 0 myself?

Any pointers gratefully accepted,

Eric

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 of 2012-09-16 on pellet