Units and types

Units

Comparisons, startOf and endOf share one set of units. Each also goes by its plural and the aliases below. Aliases are case-sensitive, as in Day.js: M is month, m minute.

Unit	Aliases	Kind
year	years, y	calendar
month	months, M	calendar
week	weeks, w	calendar
day	days, d	calendar
hour	hours, h	time
minute	minutes, m, min, mins	time
second	seconds, s, sec, secs	time
millisecond	milliseconds, ms	time

Units follow the receiver:

• PlainDate takes calendar units: it has no clock.
• Instant takes time units: it has no calendar.
• PlainDateTime and ZonedDateTime take both.

Chronos(today).isSame(deadline, "M"); // fine
Chronos(today).isSame(deadline, "hour"); // type error: a PlainDate has no hours

Exported types

All are type-only exports from chronos-temporal.

Type	What it is
SupportedTemporalType	PlainDate | PlainDateTime | ZonedDateTime | Instant
CalendarUnit	Calendar units, by name or alias
TimeUnit	Time units, by name or alias
Unit	CalendarUnit | TimeUnit
UnitOf<T>	The units a value of type T supports
BetweenOptions<T>	Options of isBetween and range checks
ZonedParseOptions	Options of Chronos.parse for zoned types
Query<T>	The query methods
Manipulate<T>	The manipulate methods
Display<T>	The display methods
Range<T>	What Chronos.range returns
Parse	The signature of Chronos.parse

Chronos(value) returns Query<T> & Manipulate<T> & Display<T>, but by the contract that type never leaves the expression.

Overloads

Chronos and Chronos.range have one overload per type, so a union-typed receiver is rejected rather than widening the argument type and hiding a PlainDate-versus-ZonedDateTime mix. Narrow the value first.