While i was strongly leaning towards singular, i understand why one would expect plural. Given that seems to be pretty standard in wild, i am fine changing it as well.
What mostly put me off about was that we'd end up with `Time.add(t, 3, :minute)` vs `Time.shift(t, minutes: 3)`, which after all, maybe isn't too bad, as we can keep the plural keys exclusive to durations. Another reason for going with plurals is that it _should_ make migrating from some libraries to the standard library relatively straight forward (with the exception of microseconds). On Wednesday, March 6, 2024 at 11:07:52 PM UTC+1 José Valim wrote: > After a quick glance on other programming languages, it seems Python, > Java, Rust, and C# all have plural names. Erlang also uses plural in its > helper functions in the timer module. So we might want to follow suit. > > On Wed, Mar 6, 2024 at 23:03 José Valim <jose....@dashbit.co> wrote: > >> We discussed plural vs singular and settled on singular so it mirrors the >> calendar types. Thoughts? >> >> On Wed, Mar 6, 2024 at 23:01 Panagiotis Nezis <pne...@gmail.com> wrote: >> >>> +1 for this, awesome work Theo. Shifting dates/timestamps is such a >>> common operation and a standard implementation would be beneficial for >>> everybody. >>> >>> PS. I would expect plural in the duration fields. >>> >>> On Wed, Mar 6, 2024 at 8:23 PM José Valim <jose....@dashbit.co> wrote: >>> >>>> The main argument for having it in core is: >>>> >>>> * It integrates directly with the Calendar behaviour >>>> * We could provide built-in sigils in the future to create readable >>>> durations, such as ~P[3 hours and 10 minutes] >>>> * Postgrex, Explorer, CLDR, etc all implement their own version of >>>> durations >>>> >>>> Arguments for not having it in core: it happens that all of the >>>> arguments above can also be solved without adding Duration to Elixir and, >>>> instead, by creating a custom library: >>>> >>>> * A separate library could extend the calendar behaviour with shift_* >>>> functions >>>> * Third-party sigils can also be provided by libraries >>>> * Postgrex, Explorer, and CLDR could create or use a package with a >>>> duratio type shared across them all >>>> >>>> I would love to hear the community thoughts. >>>> >>>> On Wed, Mar 6, 2024 at 7:16 PM 'Theo Fiedler' via elixir-lang-core < >>>> elixir-l...@googlegroups.com> wrote: >>>> >>>>> *Preface* >>>>> >>>>> We currently have `add/2-3` to manipulate calendar types in the >>>>> standard library. These functions allow adding a specified amount of time >>>>> of given unit to a date/time. The standard library currently misses means >>>>> to apply more complex, or logical *durations *to calendar types. e.g. >>>>> adding a month, a week, or one month and 10 days to a date. >>>>> >>>>> *Reasons for it* >>>>> >>>>> While similar functionality exists in libraries, such as CLDR, >>>>> Timex, Tox, adding this functionality to the standard library has already >>>>> been requested and discussed at multiple occasions over the past years. >>>>> To >>>>> list a few examples: >>>>> >>>>> - https://github.com/elixir-lang/elixir/pull/10199 >>>>> - >>>>> https://elixirforum.com/t/get-date-n-months-years-in-the-past/48346/3 >>>>> - >>>>> https://elixir-lang.slack.com/archives/C0HEX82NR/p1709581478427009?thread_ts=1709368588.334759&cid=C0HEX82NR >>>>> >>>>> Furthermore the shift behaviour in the extremely popular library Timex >>>>> changed <https://github.com/bitwalker/timex/issues/731> in Elixir >= >>>>> 1.14.3 which may have complicated the mostly lean and non-breaking >>>>> language >>>>> upgrade Elixir has to offer. >>>>> >>>>> Elixir has a great set of modules and functions that deal with date >>>>> and time, the APIs are consistent and `shift/2-3` should fit right in, >>>>> solving many standard needs of various industries, be it for reporting, >>>>> appointments, events, finance... the list goes on, engineers probably >>>>> face >>>>> the need to shift time logically more often than not in their careers. >>>>> >>>>> *Technical details* >>>>> >>>>> Duration >>>>> A date or time must be shifted by a *duration*. There is an ISO8601 >>>>> for durations <https://en.wikipedia.org/wiki/ISO_8601#Durations>, >>>>> which the initial implementation is loosely following. The structure of a >>>>> Duration lives in its own module with its own set of functions to create >>>>> and manipulate durations. One example of where it diverts from the ISO >>>>> standard, is that it implements microseconds. Microseconds in a >>>>> *duration* are stored in the same format as in the time calendar >>>>> types, meaning they integrate well and provide consistency. >>>>> >>>>> Shift >>>>> The shift behaviour is implemented as a callback on Calendar and >>>>> supported by all calendar types: Date, DateTime, NaiveDateTime and Time. >>>>> Date, Time and NaiveDateTime each have their own implementation of a >>>>> "shift", while DateTime gets converted to a NaiveDateTime before applying >>>>> the shift, and is then rebuilt to a DateTime in its original timezone. >>>>> `shift/2-3` also has guaranteed output types (which isn't a given in many >>>>> libraries) and follows the consistent API which is established in the >>>>> calendar modules. >>>>> >>>>> Find the current state of the implementation here: >>>>> https://github.com/elixir-lang/elixir/pull/13385 >>>>> >>>>> *Benchmarks* >>>>> >>>>> There are some benchmarks + StreamData tests in the PR description. >>>>> >>>>> *Outlook* >>>>> >>>>> *After *adding the Duration type and shift behaviour to the standard >>>>> library, the following things could be explored and derived from the >>>>> initial work: >>>>> >>>>> >>>>> - Implementing a protocol that allows Duration to be applied to >>>>> any data type, not just dates and times. >>>>> - A range-like data type that allows us to do recurring constructs >>>>> on any data type. For example, Duration.interval(~D[2000-01-01], >>>>> month: 1), when iterated, would emit {:ok, date} | {:error, start, >>>>> duration, reason} entries >>>>> - A sigil for easy creation of durations: ~P[3 hours and 10 >>>>> minutes] >>>>> - Making it so add/2-3 reuses the shift_* functions >>>>> >>>>> *Reasons against it* >>>>> >>>>> While I am convinced that adding `shift/2-3` to the standard library >>>>> would be very beneficial, nothing really speaks against the points >>>>> mentioned above to be implemented in a library instead. However, >>>>> something >>>>> as crucial and central as date/time manipulation should still be part of >>>>> the standard library, negating the risk of breaking changes, inconsistent >>>>> behaviour and outdated or too unique ergonomics which aren't widely >>>>> applicable, unlike what should be part of the standard library. >>>>> >>>>> Many thanks to @jose & @kip for the initial reviews and everyone in >>>>> advance taking the time to read the proposal! >>>>> >>>>> Looking forward to hear other peoples ideas and opinions on the >>>>> subject! >>>>> >>>>> -- >>>>> 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 elixir-lang-co...@googlegroups.com. >>>>> To view this discussion on the web visit >>>>> https://groups.google.com/d/msgid/elixir-lang-core/cb0ed628-3848-4de0-aa13-c0f4761e4d99n%40googlegroups.com >>>>> >>>>> <https://groups.google.com/d/msgid/elixir-lang-core/cb0ed628-3848-4de0-aa13-c0f4761e4d99n%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 elixir-lang-co...@googlegroups.com. >>>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/elixir-lang-core/CAGnRm4%2BNmFsMhbkRubMjnmM8c_Amq8DgmKCJtzJ1GEuM4-sVgw%40mail.gmail.com >>>> >>>> <https://groups.google.com/d/msgid/elixir-lang-core/CAGnRm4%2BNmFsMhbkRubMjnmM8c_Amq8DgmKCJtzJ1GEuM4-sVgw%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 elixir-lang-co...@googlegroups.com. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/elixir-lang-core/CAPxxbtjvFwnMXe134RR8wjnYk%2Bm-%2BF%2BO_79dWKk3G-bt99Ln%2Bw%40mail.gmail.com >>> >>> <https://groups.google.com/d/msgid/elixir-lang-core/CAPxxbtjvFwnMXe134RR8wjnYk%2Bm-%2BF%2BO_79dWKk3G-bt99Ln%2Bw%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. 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