getDurationUnit

Signature

getDurationUnit(value: string, unit: keyof DurationLike | DateTimeUnit): number | null

Read a single component out of an ISO 8601 duration string.

• Uses Temporal.Duration.from and reads the named field directly — this is the value as stored, not a converted total: getDurationUnit(“PT90M”, “hours”) is 0, because “PT90M” holds 90 in its minutes field and nothing in its hours field. Use totalDuration for a converted total.
• Never needs relativeTo: reading a field is not a unit conversion, so calendar units (years/months/weeks) work here even though they require an anchor in totalDuration.
• Temporal balances fractional units at parse time, so getDurationUnit(“PT1.5H”, “minutes”) is 30 — the input’s own precision, not the caller’s spelling of it, decides the fields.
• A negative duration stores every field as negative, so this returns a negative number for each nonzero component of “-P1DT2H”, not just the leading one.
• unit accepts the plural or singular name ("hours" or "hour"), as Temporal does.
• Returns null when value is not a valid duration string or unit is not a valid DateTimeDurationUnit.

Parameters

Parameter	Type	Description
value	string	ISO 8601 duration string
unit	keyof DurationLike | DateTimeUnit	DateTimeDurationUnit to read (“years” | “months” | “weeks” | “days” | “hours” | “minutes” | “seconds” | “milliseconds” | “microseconds” | “nanoseconds”, or the singular name)

Returns

the component’s value, or null on invalid input

Related types

• DateTimeDurationUnit

Examples

import { getDurationUnit } from "@northguild/gmt/duration/calculate";

getDurationUnit("P1DT2H30M", "hours") // 2

value

output

 

Source

duration/calculate/getDurationUnit.ts