formatRelativeTime

function · packages/primitives/src/time/relative.ts:7

function formatRelativeTime(from: Date, to: Date, locale?: string): string

Relative time as a pure function: picks the unit (seconds through years) and delegates the wording to Intl.RelativeTimeFormat, so locales come from the platform, not a phrase table. from is the earlier moment; swap the arguments for future phrasing ("in 3 days").