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978 lines (918 loc) · 47.2 KB
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<!DOCTYPE html>
<meta charset="utf8">
<emu-clause id="sec-temporal-plaindate-objects">
<h1>Temporal.PlainDate Objects</h1>
<p>
A Temporal.PlainDate object is an Object that contains integers corresponding to a
particular year, month, and day in the ISO8601 calendar, as well as an Object value used to
interpret those integers in a particular calendar.
</p>
<emu-clause id="sec-temporal-plaindate-constructor">
<h1>The Temporal.PlainDate Constructor</h1>
<p>The Temporal.PlainDate constructor:</p>
<ul>
<li>
creates and initializes a new Temporal.PlainDate object when called as a constructor.
</li>
<li>
is not intended to be called as a function and will throw an exception when called in that manner.
</li>
<li>
may be used as the value of an `extends` clause of a class definition.
Subclass constructors that intend to inherit the specified Temporal.PlainDate behaviour must
include a super call to the %Temporal.PlainDate% constructor to create and initialize subclass
instances with the necessary internal slots.
</li>
</ul>
<emu-clause id="sec-temporal.plaindate">
<h1>Temporal.PlainDate ( _isoYear_, _isoMonth_, _isoDay_ [ , _calendar_ ] )</h1>
<p>This function performs the following steps when called:</p>
<emu-alg>
1. If NewTarget is *undefined*, throw a *TypeError* exception.
1. Let _y_ be ? ToIntegerWithTruncation(_isoYear_).
1. Let _m_ be ? ToIntegerWithTruncation(_isoMonth_).
1. Let _d_ be ? ToIntegerWithTruncation(_isoDay_).
1. If _calendar_ is *undefined*, set _calendar_ to *"iso8601"*.
1. If _calendar_ is not a String, throw a *TypeError* exception.
1. Set _calendar_ to ? CanonicalizeCalendar(_calendar_).
1. If IsValidISODate(_y_, _m_, _d_) is *false*, throw a *RangeError* exception.
1. Let _isoDate_ be CreateISODateRecord(_y_, _m_, _d_).
1. Return ? CreateTemporalDate(_isoDate_, _calendar_, NewTarget).
</emu-alg>
</emu-clause>
</emu-clause>
<emu-clause id="sec-properties-of-the-temporal-plaindate-constructor">
<h1>Properties of the Temporal.PlainDate Constructor</h1>
<p>The Temporal.PlainDate constructor:</p>
<ul>
<li>has a [[Prototype]] internal slot whose value is %Function.prototype%.</li>
<li>has the following properties:</li>
</ul>
<emu-clause id="sec-temporal.plaindate.prototype">
<h1>Temporal.PlainDate.prototype</h1>
<p>The initial value of `Temporal.PlainDate.prototype` is %Temporal.PlainDate.prototype%.</p>
<p>This property has the attributes { [[Writable]]: *false*, [[Enumerable]]: *false*, [[Configurable]]: *false* }.</p>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.from">
<h1>Temporal.PlainDate.from ( _item_ [ , _options_ ] )</h1>
<p>This function performs the following steps when called:</p>
<emu-alg>
1. Return ? ToTemporalDate(_item_, _options_).
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.compare">
<h1>Temporal.PlainDate.compare ( _one_, _two_ )</h1>
<p>This function performs the following steps when called:</p>
<emu-alg>
1. Set _one_ to ? ToTemporalDate(_one_).
1. Set _two_ to ? ToTemporalDate(_two_).
1. Return 𝔽(CompareISODate(_one_.[[ISODate]], _two_.[[ISODate]])).
</emu-alg>
</emu-clause>
</emu-clause>
<emu-clause id="sec-properties-of-the-temporal-plaindate-prototype-object">
<h1>Properties of the Temporal.PlainDate Prototype Object</h1>
<p>The Temporal.PlainDate prototype object</p>
<ul>
<li>is itself an ordinary object.</li>
<li>is not a Temporal.PlainDate instance and does not have a [[InitializedTemporalDate]] internal slot.</li>
<li>has a [[Prototype]] internal slot whose value is %Object.prototype%.</li>
</ul>
<emu-note>
An ECMAScript implementation that includes the ECMA-402 Internationalization API extends this prototype with additional properties in order to represent calendar data.
</emu-note>
<emu-clause id="sec-temporal.plaindate.prototype.constructor">
<h1>Temporal.PlainDate.prototype.constructor</h1>
<p>The initial value of `Temporal.PlainDate.prototype.constructor` is %Temporal.PlainDate%.</p>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.prototype-%symbol.tostringtag%">
<h1>Temporal.PlainDate.prototype[ %Symbol.toStringTag% ]</h1>
<p>The initial value of the %Symbol.toStringTag% property is the String *"Temporal.PlainDate"*.</p>
<p>This property has the attributes { [[Writable]]: *false*, [[Enumerable]]: *false*, [[Configurable]]: *true* }.</p>
</emu-clause>
<emu-clause id="sec-get-temporal.plaindate.prototype.calendarid">
<h1>get Temporal.PlainDate.prototype.calendarId</h1>
<p>
`Temporal.PlainDate.prototype.calendarId` is an accessor property whose set accessor function is *undefined*.
Its get accessor function performs the following steps:
</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return _plainDate_.[[Calendar]].
</emu-alg>
</emu-clause>
<emu-clause id="sec-get-temporal.plaindate.prototype.era">
<h1>get Temporal.PlainDate.prototype.era</h1>
<p>
`Temporal.PlainDate.prototype.era` is an accessor property whose set accessor function is *undefined*.
Its get accessor function performs the following steps:
</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return CalendarISOToDate(_plainDate_.[[Calendar]], _plainDate_.[[ISODate]]).[[Era]].
</emu-alg>
</emu-clause>
<emu-clause id="sec-get-temporal.plaindate.prototype.erayear">
<h1>get Temporal.PlainDate.prototype.eraYear</h1>
<p>
`Temporal.PlainDate.prototype.eraYear` is an accessor property whose set accessor function is *undefined*.
Its get accessor function performs the following steps:
</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Let _result_ be CalendarISOToDate(_plainDate_.[[Calendar]], _plainDate_.[[ISODate]]).[[EraYear]].
1. If _result_ is *undefined*, return *undefined*.
1. Return 𝔽(_result_).
</emu-alg>
</emu-clause>
<emu-clause id="sec-get-temporal.plaindate.prototype.year">
<h1>get Temporal.PlainDate.prototype.year</h1>
<p>
`Temporal.PlainDate.prototype.year` is an accessor property whose set accessor function is *undefined*.
Its get accessor function performs the following steps:
</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return 𝔽(CalendarISOToDate(_plainDate_.[[Calendar]], _plainDate_.[[ISODate]]).[[Year]]).
</emu-alg>
</emu-clause>
<emu-clause id="sec-get-temporal.plaindate.prototype.month">
<h1>get Temporal.PlainDate.prototype.month</h1>
<p>
`Temporal.PlainDate.prototype.month` is an accessor property whose set accessor function is *undefined*.
Its get accessor function performs the following steps:
</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return 𝔽(CalendarISOToDate(_plainDate_.[[Calendar]], _plainDate_.[[ISODate]]).[[Month]]).
</emu-alg>
</emu-clause>
<emu-clause id="sec-get-temporal.plaindate.prototype.monthcode">
<h1>get Temporal.PlainDate.prototype.monthCode</h1>
<p>
`Temporal.PlainDate.prototype.monthCode` is an accessor property whose set accessor function is *undefined*.
Its get accessor function performs the following steps:
</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return CalendarISOToDate(_plainDate_.[[Calendar]], _plainDate_.[[ISODate]]).[[MonthCode]].
</emu-alg>
</emu-clause>
<emu-clause id="sec-get-temporal.plaindate.prototype.day">
<h1>get Temporal.PlainDate.prototype.day</h1>
<p>
`Temporal.PlainDate.prototype.day` is an accessor property whose set accessor function is *undefined*.
Its get accessor function performs the following steps:
</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return 𝔽(CalendarISOToDate(_plainDate_.[[Calendar]], _plainDate_.[[ISODate]]).[[Day]]).
</emu-alg>
</emu-clause>
<emu-clause id="sec-get-temporal.plaindate.prototype.dayofweek">
<h1>get Temporal.PlainDate.prototype.dayOfWeek</h1>
<p>
`Temporal.PlainDate.prototype.dayOfWeek` is an accessor property whose set accessor function is *undefined*.
Its get accessor function performs the following steps:
</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return 𝔽(CalendarISOToDate(_plainDate_.[[Calendar]], _plainDate_.[[ISODate]]).[[DayOfWeek]]).
</emu-alg>
</emu-clause>
<emu-clause id="sec-get-temporal.plaindate.prototype.dayofyear">
<h1>get Temporal.PlainDate.prototype.dayOfYear</h1>
<p>
`Temporal.PlainDate.prototype.dayOfYear` is an accessor property whose set accessor function is *undefined*.
Its get accessor function performs the following steps:
</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return 𝔽(CalendarISOToDate(_plainDate_.[[Calendar]], _plainDate_.[[ISODate]]).[[DayOfYear]]).
</emu-alg>
</emu-clause>
<emu-clause id="sec-get-temporal.plaindate.prototype.weekofyear">
<h1>get Temporal.PlainDate.prototype.weekOfYear</h1>
<p>
`Temporal.PlainDate.prototype.weekOfYear` is an accessor property whose set accessor function is *undefined*.
Its get accessor function performs the following steps:
</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Let _result_ be CalendarISOToDate(_plainDate_.[[Calendar]], _plainDate_.[[ISODate]]).[[WeekOfYear]].[[Week]].
1. If _result_ is *undefined*, return *undefined*.
1. Return 𝔽(_result_).
</emu-alg>
</emu-clause>
<emu-clause id="sec-get-temporal.plaindate.prototype.yearofweek">
<h1>get Temporal.PlainDate.prototype.yearOfWeek</h1>
<p>
`Temporal.PlainDate.prototype.yearOfWeek` is an accessor property whose set accessor function is *undefined*.
Its get accessor function performs the following steps:
</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Let _result_ be CalendarISOToDate(_plainDate_.[[Calendar]], _plainDate_.[[ISODate]]).[[WeekOfYear]].[[Year]].
1. If _result_ is *undefined*, return *undefined*.
1. Return 𝔽(_result_).
</emu-alg>
</emu-clause>
<emu-clause id="sec-get-temporal.plaindate.prototype.daysinweek">
<h1>get Temporal.PlainDate.prototype.daysInWeek</h1>
<p>
`Temporal.PlainDate.prototype.daysInWeek` is an accessor property whose set accessor function is *undefined*.
Its get accessor function performs the following steps:
</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return 𝔽(CalendarISOToDate(_plainDate_.[[Calendar]], _plainDate_.[[ISODate]]).[[DaysInWeek]]).
</emu-alg>
</emu-clause>
<emu-clause id="sec-get-temporal.plaindate.prototype.daysinmonth">
<h1>get Temporal.PlainDate.prototype.daysInMonth</h1>
<p>
`Temporal.PlainDate.prototype.daysInMonth` is an accessor property whose set accessor function is *undefined*.
Its get accessor function performs the following steps:
</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return 𝔽(CalendarISOToDate(_plainDate_.[[Calendar]], _plainDate_.[[ISODate]]).[[DaysInMonth]]).
</emu-alg>
</emu-clause>
<emu-clause id="sec-get-temporal.plaindate.prototype.daysinyear">
<h1>get Temporal.PlainDate.prototype.daysInYear</h1>
<p>
`Temporal.PlainDate.prototype.daysInYear` is an accessor property whose set accessor function is *undefined*.
Its get accessor function performs the following steps:
</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return 𝔽(CalendarISOToDate(_plainDate_.[[Calendar]], _plainDate_.[[ISODate]]).[[DaysInYear]]).
</emu-alg>
</emu-clause>
<emu-clause id="sec-get-temporal.plaindate.prototype.monthsinyear">
<h1>get Temporal.PlainDate.prototype.monthsInYear</h1>
<p>
`Temporal.PlainDate.prototype.monthsInYear` is an accessor property whose set accessor function is *undefined*.
Its get accessor function performs the following steps:
</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return 𝔽(CalendarISOToDate(_plainDate_.[[Calendar]], _plainDate_.[[ISODate]]).[[MonthsInYear]]).
</emu-alg>
</emu-clause>
<emu-clause id="sec-get-temporal.plaindate.prototype.inleapyear">
<h1>get Temporal.PlainDate.prototype.inLeapYear</h1>
<p>
`Temporal.PlainDate.prototype.inLeapYear` is an accessor property whose set accessor function is *undefined*.
Its get accessor function performs the following steps:
</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return CalendarISOToDate(_plainDate_.[[Calendar]], _plainDate_.[[ISODate]]).[[InLeapYear]].
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.prototype.toplainyearmonth">
<h1>Temporal.PlainDate.prototype.toPlainYearMonth ( )</h1>
<p>This method performs the following steps when called:</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Let _calendar_ be _plainDate_.[[Calendar]].
1. Let _fields_ be ISODateToFields(_calendar_, _plainDate_.[[ISODate]], ~date~).
1. Let _isoDate_ be ? CalendarYearMonthFromFields(_calendar_, _fields_, ~constrain~).
1. Return ! CreateTemporalYearMonth(_isoDate_, _calendar_).
1. NOTE: The call to CalendarYearMonthFromFields is necessary in order to create a PlainYearMonth object with the [[Day]] field of the [[ISODate]] internal slot set correctly.
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.prototype.toplainmonthday">
<h1>Temporal.PlainDate.prototype.toPlainMonthDay ( )</h1>
<p>This method performs the following steps when called:</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Let _calendar_ be _plainDate_.[[Calendar]].
1. Let _fields_ be ISODateToFields(_calendar_, _plainDate_.[[ISODate]], ~date~).
1. Let _isoDate_ be ? CalendarMonthDayFromFields(_calendar_, _fields_, ~constrain~).
1. Return ! CreateTemporalMonthDay(_isoDate_, _calendar_).
1. NOTE: The call to CalendarMonthDayFromFields is necessary in order to create a PlainMonthDay object with the [[Year]] field of the [[ISODate]] internal slot set correctly.
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.prototype.add">
<h1>Temporal.PlainDate.prototype.add ( _temporalDurationLike_ [ , _options_ ] )</h1>
<p>This method performs the following steps when called:</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return ? AddDurationToDate(~add~, _plainDate_, _temporalDurationLike_, _options_).
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.prototype.subtract">
<h1>Temporal.PlainDate.prototype.subtract ( _temporalDurationLike_ [ , _options_ ] )</h1>
<p>This method performs the following steps when called:</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return ? AddDurationToDate(~subtract~, _plainDate_, _temporalDurationLike_, _options_).
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.prototype.with">
<h1>Temporal.PlainDate.prototype.with ( _temporalDateLike_ [ , _options_ ] )</h1>
<p>This method performs the following steps when called:</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. If ? IsPartialTemporalObject(_temporalDateLike_) is *false*, throw a *TypeError* exception.
1. Let _calendar_ be _plainDate_.[[Calendar]].
1. Let _fields_ be ISODateToFields(_calendar_, _plainDate_.[[ISODate]], ~date~).
1. Let _partialDate_ be ? PrepareCalendarFields(_calendar_, _temporalDateLike_, « ~year~, ~month~, ~month-code~, ~day~ », « », ~partial~).
1. Set _fields_ to CalendarMergeFields(_calendar_, _fields_, _partialDate_).
1. Let _resolvedOptions_ be ? GetOptionsObject(_options_).
1. Let _overflow_ be ? GetTemporalOverflowOption(_resolvedOptions_).
1. Let _isoDate_ be ? CalendarDateFromFields(_calendar_, _fields_, _overflow_).
1. Return ! CreateTemporalDate(_isoDate_, _calendar_).
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.prototype.withcalendar">
<h1>Temporal.PlainDate.prototype.withCalendar ( _calendarLike_ )</h1>
<p>This method performs the following steps when called:</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Let _calendar_ be ? ToTemporalCalendarIdentifier(_calendarLike_).
1. Return ! CreateTemporalDate(_plainDate_.[[ISODate]], _calendar_).
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.prototype.until">
<h1>Temporal.PlainDate.prototype.until ( _other_ [ , _options_ ] )</h1>
<p>This method performs the following steps when called:</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return ? DifferenceTemporalPlainDate(~until~, _plainDate_, _other_, _options_).
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.prototype.since">
<h1>Temporal.PlainDate.prototype.since ( _other_ [ , _options_ ] )</h1>
<p>This method performs the following steps when called:</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return ? DifferenceTemporalPlainDate(~since~, _plainDate_, _other_, _options_).
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.prototype.equals">
<h1>Temporal.PlainDate.prototype.equals ( _other_ )</h1>
<p>This method performs the following steps when called:</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Set _other_ to ? ToTemporalDate(_other_).
1. If CompareISODate(_plainDate_.[[ISODate]], _other_.[[ISODate]]) ≠ 0, return *false*.
1. Return CalendarEquals(_plainDate_.[[Calendar]], _other_.[[Calendar]]).
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.prototype.toplaindatetime">
<h1>Temporal.PlainDate.prototype.toPlainDateTime ( [ _temporalTime_ ] )</h1>
<p>This method performs the following steps when called:</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Let _time_ be ? ToTimeRecordOrMidnight(_temporalTime_).
1. Let _isoDateTime_ be CombineISODateAndTimeRecord(_plainDate_.[[ISODate]], _time_).
1. Return ? CreateTemporalDateTime(_isoDateTime_, _plainDate_.[[Calendar]]).
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.prototype.tozoneddatetime">
<h1>Temporal.PlainDate.prototype.toZonedDateTime ( _item_ )</h1>
<p>This method performs the following steps when called:</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. If _item_ is an Object, then
1. Let _timeZoneLike_ be ? Get(_item_, *"timeZone"*).
1. If _timeZoneLike_ is *undefined*, then
1. Let _timeZone_ be ? ToTemporalTimeZoneIdentifier(_item_).
1. Let _temporalTime_ be *undefined*.
1. Else,
1. Let _timeZone_ be ? ToTemporalTimeZoneIdentifier(_timeZoneLike_).
1. Let _temporalTime_ be ? Get(_item_, *"plainTime"*).
1. Else,
1. Let _timeZone_ be ? ToTemporalTimeZoneIdentifier(_item_).
1. Let _temporalTime_ be *undefined*.
1. If _temporalTime_ is *undefined*, then
1. Let _epochNs_ be ? GetStartOfDay(_timeZone_, _plainDate_.[[ISODate]]).
1. Else,
1. Set _temporalTime_ to ? ToTemporalTime(_temporalTime_).
1. Let _isoDateTime_ be CombineISODateAndTimeRecord(_plainDate_.[[ISODate]], _temporalTime_.[[Time]]).
1. If ISODateTimeWithinLimits(_isoDateTime_) is *false*, throw a *RangeError* exception.
1. Let _epochNs_ be ? GetEpochNanosecondsFor(_timeZone_, _isoDateTime_, ~compatible~).
1. Return ! CreateTemporalZonedDateTime(_epochNs_, _timeZone_, _plainDate_.[[Calendar]]).
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.prototype.tostring">
<h1>Temporal.PlainDate.prototype.toString ( [ _options_ ] )</h1>
<p>This method performs the following steps when called:</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Let _resolvedOptions_ be ? GetOptionsObject(_options_).
1. Let _showCalendar_ be ? GetTemporalShowCalendarNameOption(_resolvedOptions_).
1. Return TemporalDateToString(_plainDate_, _showCalendar_).
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.prototype.tolocalestring">
<h1>Temporal.PlainDate.prototype.toLocaleString ( [ _locales_ [ , _options_ ] ] )</h1>
<p>
An ECMAScript implementation that includes the ECMA-402 Internationalization API must implement this method as specified in the ECMA-402 specification.
If an ECMAScript implementation does not include the ECMA-402 API the following specification of this method is used.
</p>
<p>The meanings of the optional parameters to this method are defined in the ECMA-402 specification; implementations that do not include ECMA-402 support must not use those parameter positions for anything else.</p>
<p>This method performs the following steps when called:</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return TemporalDateToString(_plainDate_, ~auto~).
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.prototype.tojson">
<h1>Temporal.PlainDate.prototype.toJSON ( )</h1>
<p>This method performs the following steps when called:</p>
<emu-alg>
1. Let _plainDate_ be the *this* value.
1. Perform ? RequireInternalSlot(_plainDate_, [[InitializedTemporalDate]]).
1. Return TemporalDateToString(_plainDate_, ~auto~).
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal.plaindate.prototype.valueof">
<h1>Temporal.PlainDate.prototype.valueOf ( )</h1>
<p>This method performs the following steps when called:</p>
<emu-alg>
1. Throw a *TypeError* exception.
</emu-alg>
<emu-note>
<p>
This method always throws, because in the absence of `valueOf()`, expressions with arithmetic operators such as `plainDate1 > plainDate2` would fall back to being equivalent to `plainDate1.toString() > plainDate2.toString()`.
Lexicographical comparison of serialized strings might not seem obviously wrong, because the result would sometimes be correct.
Implementations are encouraged to phrase the error message to point users to `Temporal.PlainDate.compare()`, `Temporal.PlainDate.prototype.equals()`, and/or `Temporal.PlainDate.prototype.toString()`.
</p>
</emu-note>
</emu-clause>
</emu-clause>
<emu-clause id="sec-properties-of-temporal-plaindate-instances">
<h1>Properties of Temporal.PlainDate Instances</h1>
<p>
Temporal.PlainDate instances are ordinary objects that inherit properties from the %Temporal.PlainDate.prototype% intrinsic object.
Temporal.PlainDate instances are initially created with the internal slots described in <emu-xref href="#table-internal-slots-of-temporaldate-instances"></emu-xref>.
</p>
<emu-table id="table-internal-slots-of-temporaldate-instances" caption="Internal Slots of Temporal.PlainDate Instances">
<table>
<tr>
<th>
Internal Slot
</th>
<th>
Description
</th>
</tr>
<tr>
<td>
[[InitializedTemporalDate]]
</td>
<td>
The only specified use of this slot is for distinguishing Temporal.PlainDate instances from other objects.
</td>
</tr>
<tr>
<td>
[[ISODate]]
</td>
<td>
An ISO Date Record.
</td>
</tr>
<tr>
<td>
[[Calendar]]
</td>
<td>
A calendar type.
</td>
</tr>
</table>
</emu-table>
</emu-clause>
<emu-clause id="sec-temporal-plaindate-abstract-ops">
<h1>Abstract Operations for Temporal.PlainDate Objects</h1>
<emu-clause id="sec-temporal-iso-date-records">
<h1>ISO Date Records</h1>
<p>
An <dfn variants="ISO Date Records">ISO Date Record</dfn> is a Record value used to represent a valid calendar date in the ISO 8601 calendar, although the year may be outside of the allowed range for Temporal.
ISO Date Records are produced by the abstract operation CreateISODateRecord.
For any ISO Date Record _d_, IsValidISODate(_d_.[[Year]], _d_.[[Month]], _d_.[[Day]]) must return *true*.
</p>
<p>ISO Date Records have the fields listed in <emu-xref href="#table-temporal-iso-date-record-fields"></emu-xref>.</p>
<emu-table id="table-temporal-iso-date-record-fields" caption="ISO Date Record Fields">
<table class="real-table">
<tr>
<th>Field Name</th>
<th>Value</th>
<th>Meaning</th>
</tr>
<tr>
<td>[[Year]]</td>
<td>an integer</td>
<td>
The year in the ISO 8601 calendar.
</td>
</tr>
<tr>
<td>[[Month]]</td>
<td>an integer between 1 and 12, inclusive</td>
<td>
The number of the month in the ISO 8601 calendar.
</td>
</tr>
<tr>
<td>[[Day]]</td>
<td>an integer between 1 and 31, inclusive</td>
<td>
The number of the day of the month in the ISO 8601 calendar.
</td>
</tr>
</table>
</emu-table>
</emu-clause>
<emu-clause id="sec-temporal-create-iso-date-record" type="abstract operation">
<h1>
CreateISODateRecord (
_year_: an integer,
_month_: an integer between 1 and 12 inclusive,
_day_: an integer between 1 and 31 inclusive,
): an ISO Date Record
</h1>
<dl class="header">
<dt>description</dt>
<dd>It creates an ISO Date Record from the given _year_, _month_, and _day_ values.</dd>
</dl>
<emu-alg>
1. Assert: IsValidISODate(_year_, _month_, _day_) is *true*.
1. Return ISO Date Record { [[Year]]: _year_, [[Month]]: _month_, [[Day]]: _day_ }.
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal-createtemporaldate" type="abstract operation">
<h1>
CreateTemporalDate (
_isoDate_: an ISO Date Record,
_calendar_: a calendar type,
optional _newTarget_: a constructor,
): either a normal completion containing a Temporal.PlainDate or a throw completion
</h1>
<dl class="header">
<dt>description</dt>
<dd>It creates a Temporal.PlainDate instance and fills the internal slots with valid values.</dd>
</dl>
<emu-alg>
1. If ISODateWithinLimits(_isoDate_) is *false*, throw a *RangeError* exception.
1. If _newTarget_ is not present, set _newTarget_ to %Temporal.PlainDate%.
1. Let _object_ be ? OrdinaryCreateFromConstructor(_newTarget_, *"%Temporal.PlainDate.prototype%"*, « [[InitializedTemporalDate]], [[ISODate]], [[Calendar]] »).
1. Set _object_.[[ISODate]] to _isoDate_.
1. Set _object_.[[Calendar]] to _calendar_.
1. Return _object_.
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal-totemporaldate" type="abstract operation">
<h1>
ToTemporalDate (
_item_: an ECMAScript language value,
optional _options_: an ECMAScript language value,
): either a normal completion containing a Temporal.PlainDate or a throw completion
</h1>
<dl class="header">
<dt>description</dt>
<dd>Converts _item_ to a new Temporal.PlainDate instance if possible, and throws otherwise.</dd>
</dl>
<emu-alg>
1. If _options_ is not present, set _options_ to *undefined*.
1. If _item_ is an Object, then
1. If _item_ has an [[InitializedTemporalDate]] internal slot, then
1. Let _resolvedOptions_ be ? GetOptionsObject(_options_).
1. Perform ? GetTemporalOverflowOption(_resolvedOptions_).
1. Return ! CreateTemporalDate(_item_.[[ISODate]], _item_.[[Calendar]]).
1. If _item_ has an [[InitializedTemporalZonedDateTime]] internal slot, then
1. Let _isoDateTime_ be GetISODateTimeFor(_item_.[[TimeZone]], _item_.[[EpochNanoseconds]]).
1. Let _resolvedOptions_ be ? GetOptionsObject(_options_).
1. Perform ? GetTemporalOverflowOption(_resolvedOptions_).
1. Return ! CreateTemporalDate(_isoDateTime_.[[ISODate]], _item_.[[Calendar]]).
1. If _item_ has an [[InitializedTemporalDateTime]] internal slot, then
1. Let _resolvedOptions_ be ? GetOptionsObject(_options_).
1. Perform ? GetTemporalOverflowOption(_resolvedOptions_).
1. Return ! CreateTemporalDate(_item_.[[ISODateTime]].[[ISODate]], _item_.[[Calendar]]).
1. Let _calendar_ be ? GetTemporalCalendarIdentifierWithISODefault(_item_).
1. Let _fields_ be ? PrepareCalendarFields(_calendar_, _item_, « ~year~, ~month~, ~month-code~, ~day~ », «», «»).
1. Let _resolvedOptions_ be ? GetOptionsObject(_options_).
1. Let _overflow_ be ? GetTemporalOverflowOption(_resolvedOptions_).
1. Let _isoDate_ be ? CalendarDateFromFields(_calendar_, _fields_, _overflow_).
1. Return ! CreateTemporalDate(_isoDate_, _calendar_).
1. If _item_ is not a String, throw a *TypeError* exception.
1. Let _result_ be ? ParseISODateTime(_item_, « |TemporalDateTimeString[~Zoned]| »).
1. Let _calendar_ be _result_.[[Calendar]].
1. If _calendar_ is ~empty~, set _calendar_ to *"iso8601"*.
1. Set _calendar_ to ? CanonicalizeCalendar(_calendar_).
1. Let _resolvedOptions_ be ? GetOptionsObject(_options_).
1. Perform ? GetTemporalOverflowOption(_resolvedOptions_).
1. Let _isoDate_ be CreateISODateRecord(_result_.[[Year]], _result_.[[Month]], _result_.[[Day]]).
1. Return ? CreateTemporalDate(_isoDate_, _calendar_).
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal-comparesurpasses" type="abstract operation">
<h1>
CompareSurpasses (
_sign_: either -1 or 1,
_year_: an integer,
_monthOrCode_: either an integer or a month code,
_day_: an integer,
_target_: a Calendar Date Record,
): a Boolean
</h1>
<dl class="header">
<dt>description</dt>
<dd>
The return value indicates whether the calendar date formed by _year_, _monthOrCode_, and _day_, which need not exist, surpasses _target_ in the direction denoted by _sign_.
</dd>
</dl>
<emu-alg>
1. If _year_ ≠ _target_.[[Year]], then
1. If _sign_ × (_year_ - _target_.[[Year]]) > 0, return *true*.
1. Else if _monthOrCode_ is a month code and _monthOrCode_ is not _target_.[[MonthCode]], then
1. If _sign_ > 0, then
1. If _monthOrCode_ is lexicographically greater than _target_.[[MonthCode]], return *true*.
1. Else,
1. If _target_.[[MonthCode]] is lexicographically greater than _monthOrCode_, return *true*.
1. Else if _monthOrCode_ is an integer and _monthOrCode_ ≠ _target_.[[Month]], then
1. If _sign_ × (_monthOrCode_ - _target_.[[Month]]) > 0, return *true*.
1. Else if _day_ ≠ _target_.[[Day]], then
1. If _sign_ × (_day_ - _target_.[[Day]]) > 0, return *true*.
1. Return *false*.
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal-isodatesurpasses" type="abstract operation">
<h1>
ISODateSurpasses (
_sign_: either -1 or 1,
_baseDate_: an ISO Date Record,
_isoDate2_: an ISO Date Record,
_years_: an integer,
_months_: an integer,
_weeks_: an integer,
_days_: an integer,
): a Boolean
</h1>
<dl class="header">
<dt>description</dt>
<dd>
The return value indicates whether the date _isoDate1_, the result of adding the duration denoted by _years_, _months_, _weeks_, and _days_ to _baseDate_, surpasses _isoDate2_ in the direction denoted by _sign_.
If _weeks_ and _days_ are both zero, then _isoDate1_ need not exist (for example, it could be February 30).
Note that this operation is specific to date difference calculations and is not the same as CompareISODate.
</dd>
</dl>
<emu-alg>
1. Let _parts_ be CalendarISOToDate(*"iso8601"*, _baseDate_).
1. Let _target_ be CalendarISOToDate(*"iso8601"*, _isoDate2_).
1. Let _y0_ be _parts_.[[Year]] + _years_.
1. If CompareSurpasses(_sign_, _y0_, _parts_.[[MonthCode]], _parts_.[[Day]], _target_) is *true*, return *true*.
1. If _months_ = 0, return *false*.
1. Let _m0_ be _parts_.[[Month]] + _months_.
1. Let _monthsAdded_ be BalanceISOYearMonth(_y0_, _m0_).
1. If CompareSurpasses(_sign_, _monthsAdded_.[[Year]], _monthsAdded_.[[Month]], _parts_.[[Day]], _target_) is *true*, return *true*.
1. If _weeks_ = 0 and _days_ = 0, return *false*.
1. Let _regulatedDate_ be ! RegulateISODate(_monthsAdded_.[[Year]], _monthsAdded_.[[Month]], _parts_.[[Day]], ~constrain~).
1. Let _daysInWeek_ be 7.
1. Let _balancedDate_ be AddDaysToISODate(_regulatedDate_, _daysInWeek_ * _weeks_ + _days_).
1. Return CompareSurpasses(_sign_, _balancedDate_.[[Year]], _balancedDate_.[[Month]], _balancedDate_.[[Day]], _target_).
</emu-alg>
<emu-note>
<p>This operation intentionally uses overflow ~constrain~ when regulating the year-month. As a result, adding the duration returned by `.since` or `.until` to _baseDate_ may cause a *RangeError* exception when _overflow_ is ~reject~.</p>
</emu-note>
</emu-clause>
<emu-clause id="sec-temporal-regulateisodate" type="abstract operation">
<h1>
RegulateISODate (
_year_: an integer,
_month_: an integer,
_day_: an integer,
_overflow_: either ~constrain~ or ~reject~,
): either a normal completion containing an ISO Date Record or a throw completion
</h1>
<dl class="header">
<dt>description</dt>
<dd>
It performs the overflow correction specified by _overflow_ on the values _year_, _month_, and _day_, in order to arrive at a valid date in the ISO 8601 calendar, as determined by IsValidISODate.
For ~reject~, values that do not form a valid date cause an exception to be thrown.
For ~constrain~, values that do not form a valid date are independently clamped to their respective valid range in order of descending unit magnitude.
</dd>
</dl>
<emu-alg>
1. If _overflow_ is ~constrain~, then
1. Set _month_ to the result of clamping _month_ between 1 and 12.
1. Let _daysInMonth_ be ISODaysInMonth(_year_, _month_).
1. Set _day_ to the result of clamping _day_ between 1 and _daysInMonth_.
1. Else,
1. Assert: _overflow_ is ~reject~.
1. If IsValidISODate(_year_, _month_, _day_) is *false*, throw a *RangeError* exception.
1. Return CreateISODateRecord(_year_, _month_, _day_).
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal-isvalidisodate" type="abstract operation">
<h1>
IsValidISODate (
_year_: an integer,
_month_: an integer,
_day_: an integer,
): a Boolean
</h1>
<dl class="header">
<dt>description</dt>
<dd>
The return value is *true* if its arguments form a valid date in the ISO 8601 calendar, and *false* otherwise.
This includes dates that may fall outside of the allowed range for Temporal.
</dd>
</dl>
<emu-alg>
1. If _month_ < 1 or _month_ > 12, return *false*.
1. Let _daysInMonth_ be ISODaysInMonth(_year_, _month_).
1. If _day_ < 1 or _day_ > _daysInMonth_, return *false*; else return *true*.
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal-adddaystoisodate" type="abstract operation">
<h1>
AddDaysToISODate (
_isoDate_: an ISO Date Record,
_days_: an integer,
): an ISO Date Record
</h1>
<dl class="header">
<dt>description</dt>
<dd>
It adds _days_ to _isoDate_ into a valid calendar date in the ISO 8601 calendar as given by IsValidISODate, by overflowing out-of-range month or day values into the next-highest unit.
This date may be outside the range given by ISODateTimeWithinLimits.
</dd>
</dl>
<emu-alg>
1. Let _epochDays_ be ISODateToEpochDays(_isoDate_.[[Year]], _isoDate_.[[Month]] - 1, _isoDate_.[[Day]]) + _days_.
1. Let _ms_ be EpochDaysToEpochMs(_epochDays_, 0).
1. Return CreateISODateRecord(EpochTimeToEpochYear(_ms_), EpochTimeToMonthInYear(_ms_) + 1, EpochTimeToDate(_ms_)).
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal-padisoyear" type="abstract operation">
<h1>
PadISOYear (
_y_: an integer,
): a String
</h1>
<dl class="header">
<dt>description</dt>
<dd>It returns a String representation of _y_ suitable for inclusion in an ISO 8601 string, either in 4-digit format or 6-digit format with sign.</dd>
</dl>
<emu-alg>
1. If _y_ ≥ 0 and _y_ ≤ 9999, return ToZeroPaddedDecimalString(_y_, 4).
1. If _y_ > 0, let _yearSign_ be *"+"*; else let _yearSign_ be *"-"*.
1. Let _year_ be ToZeroPaddedDecimalString(abs(_y_), 6).
1. Return the string-concatenation of _yearSign_ and _year_.
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal-temporaldatetostring" type="abstract operation">
<h1>
TemporalDateToString (
_temporalDate_: a Temporal.PlainDate,
_showCalendar_: one of ~auto~, ~always~, ~never~, or ~critical~,
): a String
</h1>
<dl class="header">
<dt>description</dt>
<dd>It formats _temporalDate_ to an ISO 8601 / RFC 9557 string.</dd>
</dl>
<emu-alg>
1. Let _year_ be PadISOYear(_temporalDate_.[[ISODate]].[[Year]]).
1. Let _month_ be ToZeroPaddedDecimalString(_temporalDate_.[[ISODate]].[[Month]], 2).
1. Let _day_ be ToZeroPaddedDecimalString(_temporalDate_.[[ISODate]].[[Day]], 2).
1. Let _calendar_ be FormatCalendarAnnotation(_temporalDate_.[[Calendar]], _showCalendar_).
1. Return the string-concatenation of _year_, the code unit 0x002D (HYPHEN-MINUS), _month_, the code unit 0x002D (HYPHEN-MINUS), _day_, and _calendar_.
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal-isodatewithinlimits" type="abstract operation">
<h1>
ISODateWithinLimits (
_isoDate_: an ISO Date Record,
): a Boolean
</h1>
<dl class="header">
<dt>description</dt>
<dd>The return value is *true* if the date in the ISO 8601 calendar given by the argument is within the representable range of `Temporal.PlainDate`, and *false* otherwise.</dd>
</dl>
<emu-note>
<p>Deferring to ISODateTimeWithinLimits with an hour of 12 avoids trouble at the extremes of the representable range of Temporal.PlainDateTime, which stops just before midnight on each end.</p>
</emu-note>
<emu-alg>
1. Let _isoDateTime_ be CombineISODateAndTimeRecord(_isoDate_, NoonTimeRecord()).
1. Return ISODateTimeWithinLimits(_isoDateTime_).
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal-compareisodate" type="abstract operation">
<h1>
CompareISODate (
_isoDate1_: an ISO Date Record,
_isoDate2_: an ISO Date Record,
): one of -1, 0, or 1
</h1>
<dl class="header">
<dt>description</dt>
<dd>
It performs a comparison of the two dates denoted by _isoDate1_ and _isoDate2_ according to ISO 8601 calendar arithmetic.
</dd>
</dl>
<emu-alg>
1. If _isoDate1_.[[Year]] > _isoDate2_.[[Year]], return 1.
1. If _isoDate1_.[[Year]] < _isoDate2_.[[Year]], return -1.
1. If _isoDate1_.[[Month]] > _isoDate2_.[[Month]], return 1.
1. If _isoDate1_.[[Month]] < _isoDate2_.[[Month]], return -1.
1. If _isoDate1_.[[Day]] > _isoDate2_.[[Day]], return 1.
1. If _isoDate1_.[[Day]] < _isoDate2_.[[Day]], return -1.
1. Return 0.
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal-differencetemporalplaindate" type="abstract operation">
<h1>
DifferenceTemporalPlainDate (
_operation_: either ~since~ or ~until~,
_temporalDate_: a Temporal.PlainDate,
_other_: an ECMAScript language value,
_options_: an ECMAScript language value,
): either a normal completion containing a Temporal.Duration or a throw completion
</h1>
<dl class="header">
<dt>description</dt>
<dd>It computes the difference between the two times represented by _temporalDate_ and _other_, optionally rounds it, and returns it as a Temporal.Duration object.</dd>
</dl>
<emu-alg>
1. Set _other_ to ? ToTemporalDate(_other_).
1. If CalendarEquals(_temporalDate_.[[Calendar]], _other_.[[Calendar]]) is *false*, throw a *RangeError* exception.
1. Let _resolvedOptions_ be ? GetOptionsObject(_options_).
1. Let _settings_ be ? GetDifferenceSettings(_operation_, _resolvedOptions_, ~date~, « », ~day~, ~day~).
1. If CompareISODate(_temporalDate_.[[ISODate]], _other_.[[ISODate]]) = 0, then
1. Return ! CreateTemporalDuration(0, 0, 0, 0, 0, 0, 0, 0, 0, 0).
1. Let _dateDifference_ be CalendarDateUntil(_temporalDate_.[[Calendar]], _temporalDate_.[[ISODate]], _other_.[[ISODate]], _settings_.[[LargestUnit]]).
1. Let _duration_ be CombineDateAndTimeDuration(_dateDifference_, 0).
1. If _settings_.[[SmallestUnit]] is not ~day~ or _settings_.[[RoundingIncrement]] ≠ 1, then
1. Let _isoDateTime_ be CombineISODateAndTimeRecord(_temporalDate_.[[ISODate]], MidnightTimeRecord()).
1. Let _originEpochNs_ be GetUTCEpochNanoseconds(_isoDateTime_).
1. Let _isoDateTimeOther_ be CombineISODateAndTimeRecord(_other_.[[ISODate]], MidnightTimeRecord()).
1. Let _destEpochNs_ be GetUTCEpochNanoseconds(_isoDateTimeOther_).
1. Set _duration_ to ? RoundRelativeDuration(_duration_, _originEpochNs_, _destEpochNs_, _isoDateTime_, ~unset~, _temporalDate_.[[Calendar]], _settings_.[[LargestUnit]], _settings_.[[RoundingIncrement]], _settings_.[[SmallestUnit]], _settings_.[[RoundingMode]]).
1. Let _result_ be ! TemporalDurationFromInternal(_duration_, ~day~).
1. If _operation_ is ~since~, set _result_ to CreateNegatedTemporalDuration(_result_).
1. Return _result_.
</emu-alg>
</emu-clause>
<emu-clause id="sec-temporal-adddurationtodate" type="abstract operation">
<h1>
AddDurationToDate (
_operation_: either ~add~ or ~subtract~,
_temporalDate_: a Temporal.PlainDate,
_temporalDurationLike_: an ECMAScript language value,
_options_: an ECMAScript language value,
): either a normal completion containing a Temporal.PlainDate or a throw completion
</h1>
<dl class="header">
<dt>description</dt>
<dd>It adds/subtracts _temporalDurationLike_ to/from _temporalDate_, returning a point in time that is in the future/past relative to _temporalDate_.</dd>
</dl>
<emu-alg>
1. Let _calendar_ be _temporalDate_.[[Calendar]].
1. Let _duration_ be ? ToTemporalDuration(_temporalDurationLike_).
1. If _operation_ is ~subtract~, set _duration_ to CreateNegatedTemporalDuration(_duration_).
1. Let _dateDuration_ be ToDateDurationRecordWithoutTime(_duration_).
1. Let _resolvedOptions_ be ? GetOptionsObject(_options_).
1. Let _overflow_ be ? GetTemporalOverflowOption(_resolvedOptions_).
1. Let _result_ be ? CalendarDateAdd(_calendar_, _temporalDate_.[[ISODate]], _dateDuration_, _overflow_).
1. Return ! CreateTemporalDate(_result_, _calendar_).
</emu-alg>
</emu-clause>
</emu-clause>
</emu-clause>