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@burglekitt/gmt

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Temporal-based date and time utilities with timezone support and polyfill integration

github.com/burglekitt/gmt

burglekitt/gmt

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/** * Report whether an ISO 8601 duration is negative, zero-length, or positive. * * - Uses Temporal.Duration.from and reads .sign: -1, 0, or 1. * - Zero is its own result, not folded into the positive case — "PT0S" is 0, and so is * "-PT0S", since a negated zero is still zero. * - Needs no `relativeTo`: a duration's sign is carried on its components, not derived from * how long they measure, so calendar-unit durations answer fine. * - Returns null when `value` is not a valid ISO 8601 duration string — distinct from the 0 * a valid zero-length duration returns. * * @param value ISO 8601 duration string * @returns -1 for a negative duration, 0 for zero-length, 1 for positive, or null on invalid input * * @example getDurationSign("P1DT2H") // 1 * @example getDurationSign("-P1DT2H") // -1 * @example getDurationSign("PT0S") // 0 * @example getDurationSign("-PT0S") // 0 * @example getDurationSign("-P1Y") // -1 (no relativeTo needed) * @example getDurationSign("not a duration") // null */ export declare function getDurationSign(value: string): number | null;