Hi Arthur, If Elixir datetime is a mess, please contribute to the discussion showing use cases where you can't achieve the desired result or where the current API is confusing. Jon has just provided a great example of how to contribute, where he illustrated the problem and proposed solutions, and it is a bit unfortunate that the immediate follow up to his post is precisely the opposite.
If you can't contribute to the discussion, please abstain from posting. Thank you. On Mon, Sep 7, 2020 at 12:14 PM Arthur Collé <[email protected]> wrote: > Elixir datetime is such a mess. Even python is better and that's saying a > lot. > > On Mon, Sep 7, 2020 at 6:12 AM [email protected] <[email protected]> > wrote: > >> Hello! >> >> I'm dealing with ISO8601 strings for date times, and the current >> libraries make my use case, which is dealing with clock time but preserving >> the offset from UTC, very frustrating. >> >> Specifically (unless I'm mistaken) there is no inbuilt functions that >> allow reversible parsing of them. >> >> e.g. >> >> Given "2020-09-7T10:59:00+0100" I can parse this into a UTC DateTime and >> an offset, or a NaiveDateTime ignoring the offset, but from either of these >> I cannot reproduce "2020-09-7T10:59:00+0100". >> >> I understand that an offset is not a timezone, so I understand why by >> default it does get converted to UTC, but it does represent the clock time >> at a point in time (which is useful for historical time series data like >> I'm working with). >> >> What I propose is two options: >> >> 1) Have either/both DateTime and/or NaiveDateTime's `to_iso8601/2` >> expanded to take an offset back for the point of formatting, e.g. >> >> ``` >> {:ok, utc_dt, offset} = DateTime.from_iso8601("2020-09-7T10:59:00+0100") >> "2020-09-7T10:59:00+01:00" = DateTime.to_iso8601(utc_dt, :extended, >> offset) >> ``` >> >> 2) Have NaiveDateTime capture offset into it's struct, and allow it to be >> included when formatting date times. >> >> ``` >> {:ok, naive_dt} = NaiveDateTime.from_iso8601("2020-09-7T10:59:00+0100") >> "2020-09-7T10:59:00+01:00" = NaiveDateTime.to_iso8601(naive_dt, >> :extended_offset) >> ``` >> >> I'd be happy to work on either / both of these, but currently I have to >> use DateTime.add and manually edit the struct to get the result I want, and >> given that the inbuilt libraries are more than sufficient for all my other >> purposes the current iso8601 handling feels like it could be improved >> >> Cheers and look forward to feedback >> Jon >> >> -- >> You received this message because you are subscribed to the Google Groups >> "elixir-lang-core" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/elixir-lang-core/04e5e287-7a5b-45f1-a56c-54137bd14a23n%40googlegroups.com >> <https://groups.google.com/d/msgid/elixir-lang-core/04e5e287-7a5b-45f1-a56c-54137bd14a23n%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > -- > You received this message because you are subscribed to the Google Groups > "elixir-lang-core" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/elixir-lang-core/CAHsqzVEpdVGbvV49vVZt7bhoNvjT-%2BK%3DNnMQ%2BowmJt_A%3DqL0Uw%40mail.gmail.com > <https://groups.google.com/d/msgid/elixir-lang-core/CAHsqzVEpdVGbvV49vVZt7bhoNvjT-%2BK%3DNnMQ%2BowmJt_A%3DqL0Uw%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "elixir-lang-core" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/elixir-lang-core/CAGnRm4%2BV64Fy%2ByTF0eMh%2B_ErZhXddmsm5G%2BjRgKFnSwgtm%2BVBg%40mail.gmail.com.
