DEPR: DatetimeIndex/TimedeltaIndex constructor keywords (original) (raw)

DatetimeIndex.__new__ has constructor keywords (excluding ones present in the base class and ones already deprecated) freq, tz, ambiguous, dayfirst, yearfirst. dayfirst and yearfirst overlap with the pd.to_datetime keywords.

Could we deprecate some/all of these keywords and point users to pd.to_datetime instead?

• freq we could either exempt or make a post-construction thing by making _with_freq public.
• to_datetime has utc instead of tz. I generally like tz better than utc as a keyword, but deprecating utc might be painful. We could add tz to to_datetime and disallow passing tz-and-utc.
• Adding ambiguous to to_datetime wouldn't be too bad aside from general keyword fatigue.

(similarly TimedeltaIndex has unit and freq, unit being present in pd.to_timedelta)

cc @MarcoGorelli @mroeschke @jorisvandenbossche