Normative: Indicate ISO date 1868-10-23 as start of Meiji era#102
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Normative: Indicate ISO date 1868-10-23 as start of Meiji era#102
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ptomato
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Thanks. This correctly implements the conclusion from TG2.
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This has been updated to implement the extra conclusion from the January TG2 meeting.
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Actually now that I read it a couple more times — I think we still need to say the Meiji era started 1868-10-23, and that 1873 is 6 Meiji, otherwise it's still confusing.
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How about this? "[...] For dates up to and including ISO date 1872-12-31, years and eras identical to "gregory" are used. For later dates, the eras and ranges defined by the Japanese government are used. Note that ISO year 1873 is the 6th year of the Meiji period (starting on ISO date 1868-10-23), during which calendar reforms took place. The arithmetic year is identical to "gregory"." |
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I also realized we have to update Table 2 to make the minimum era year 6 |
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See tc39/proposal-intl-era-monthcode#102 The historical regnal period starts on 1868-10-23 but at that point the lunisolar calendar was still in use. On 1873-01-01 we start using the era code "meiji", before that we use eras and era years identical to the "gregory" calendar.
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Tests are in tc39/test262#4877 |
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… than just ISO year 1868
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Approved by TG1 20 January 2026 |
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See tc39/proposal-intl-era-monthcode#102 The historical regnal period starts on 1868-10-23 but at that point the lunisolar calendar was still in use. On 1873-01-01 we start using the era code "meiji", before that we use eras and era years identical to the "gregory" calendar.
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See tc39/proposal-intl-era-monthcode#102 The historical regnal period starts on 1868-10-23 but at that point the lunisolar calendar was still in use. On 1873-01-01 we start using the era code "meiji", before that we use eras and era years identical to the "gregory" calendar.
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See tc39/proposal-intl-era-monthcode#102 We already have a note about this in our docs, but the calendar switchover happened in Meiji 6, which means dates specified as Meiji 1-5 are unambiguously lunisolar. We're already liberal in accepting eraYears that are not in range of the era, which means we can't (and shouldn't) do much about people plugging dates specified as Meiji 1-5, but we can avoid producing such dates. Matching Temporal seems like the right call to me here. If matching Temporal here is not desired this can in theory be patched over in temporal_rs and Firefox (@hsivonen), but I feel convinced by the Temporal discussions.
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…idermonkey-reviewers,mgaudet Normative changes from <tc39/proposal-intl-era-monthcode#102>. Differential Revision: https://phabricator.services.mozilla.com/D281420
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fix #86
Previously the spec listed just the ISO year 1868 as start of the Meiji era. This change explicitly states that the Meiji era started on 1868-10-23.