Looking at the Elixir code for this, it's mostly routed to `System.convert_time_unit/3` which is a wrapper to `erlang.convert_time_unit/3`. Would it make more sense to try upstreaming this into erlang/otp?
On Wednesday, June 3, 2020 at 1:31:42 AM UTC-6 Ulisses Almeida wrote: > Well, if you implementing a fantasy world game, a week can have different > days. > > For example, in forgotten realms, a week has 10 days. > https://forgottenrealms.fandom.com/wiki/Calendar_of_Harptos > > Em qua., 3 de jun. de 2020 às 10:23, José Valim <[email protected]> > escreveu: > >> Good point Wojtek. >> >> Unfortunately this concern also applies to hours and seconds, which can >> change between calendars. I believe seconds today already operates as ISO >> seconds, so I would just document that all units are ISO units. >> >> >> On Wed, Jun 3, 2020 at 9:14 AM Wojtek Mach <[email protected]> wrote: >> >>> >>> Just a word of warning, I believe that while supporting minutes, hours, >>> and days is rather trivial since we have such fields on the structs and so >>> we could just increment them, supporting weeks is trickier - are all weeks >>> composed of 7 days or there are calendars where this is not true? Maybe se >>> should start without weeks then? Or there will be a callback for them? Leap >>> seconds may or may not be a concern too. >>> >>> On 3 Jun 2020, at 08:45, José Valim <[email protected]> wrote: >>> >>> >>> Thank you for the proposal. I believe this would be a welcome change. My >>> only question is if we should support them in the Calendar types or >>> directly on the System module. Given the System module does many >>> conversions between time units, supporting those there is slightly more >>> complicated. >>> >>> Perhaps we start with support on Calendar types and then we move it to >>> System if necessary? This means: >>> >>> 1. Support minute and hour in Time >>> 2. Support week in Date >>> 3. Support minute, hour, day and week in NaiveDateTime >>> 4. Support minute, hour, day and week in DateTime >>> >>> >>> On Wed, Jun 3, 2020 at 5:34 AM Parker Selbert <[email protected]> >>> wrote: >>> >>>> *Problem* >>>> >>>> Functions that convert or work with time units, i.e. >>>> `System.convert_time_unit/1`, `DateTime.add/3` and `Time.add/3` are >>>> limited >>>> to working with a subset of possible time units. The current subset of >>>> *named >>>> units* includes `:second`, `:millisecond`, `:microsecond`, and >>>> `:nanosecond`. It is extremely common to manipulate dates and times by >>>> larger units such as minutes, hours or days. Currently we have to convert >>>> any values to seconds and then use that to change the value, which isn't >>>> particularly explicit or expressive. For example, to get the date for one >>>> week from now I need to write: >>>> >>>> DateTime.add(DateTime.utc_now(), 7 * 24 * 60 * 60, :second) >>>> >>>> *Proposal* >>>> >>>> I propose the addition of larger pre-defined units to make conversion >>>> more expressive. Units could include some or all of the following: >>>> >>>> - `:minute` >>>> - `:hour` >>>> - `:day` >>>> - `:week` >>>> >>>> Some larger units such as `month` or `year` are not fixed or standard >>>> units and could be omitted. >>>> >>>> This enables more expressive time calculations such as "one hour from >>>> now", "one day from now", etc.: >>>> >>>> utc_now = DateTime.utc_now() >>>> DateTime.add(utc_now, 30, :minute) >>>> DateTime.add(utc_now, 1, :hour) >>>> DateTime.add(utc_now, 1, :day) >>>> >>>> In my experience it is extremely common to find module attributes or >>>> variables that declar a unit of time to make larger values comprehensible. >>>> It is much clearer to specify `1, :day` instead of `@one_day_in_seconds, >>>> :second` or something similar. >>>> >>>> -- >>>> 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/7ca22377-aadc-4e5b-a57f-ad0c52fc5ba8%40googlegroups.com >>>> >>>> <https://groups.google.com/d/msgid/elixir-lang-core/7ca22377-aadc-4e5b-a57f-ad0c52fc5ba8%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/CAGnRm4KTjtL-4K3-hj%2Bf%3D7sqHrkOJ52_C9VJ9u_Ekc35C_dY_A%40mail.gmail.com >>> >>> <https://groups.google.com/d/msgid/elixir-lang-core/CAGnRm4KTjtL-4K3-hj%2Bf%3D7sqHrkOJ52_C9VJ9u_Ekc35C_dY_A%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/FF8AE738-AF6D-4B5C-8EB9-55F86DC49D8D%40wojtekmach.pl >>> >>> <https://groups.google.com/d/msgid/elixir-lang-core/FF8AE738-AF6D-4B5C-8EB9-55F86DC49D8D%40wojtekmach.pl?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/CAGnRm4Je5HVRyv8CCKjoTSOVsh7C9eVB7ZQa9WbNN2N7KaDBgQ%40mail.gmail.com >> >> <https://groups.google.com/d/msgid/elixir-lang-core/CAGnRm4Je5HVRyv8CCKjoTSOVsh7C9eVB7ZQa9WbNN2N7KaDBgQ%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> > > > -- > *Ulisses H. F. de Almeida* > > *[email protected][email protected]* > -- 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/7bbbcba0-c85f-43d8-859f-62eb136c4110n%40googlegroups.com.
