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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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/** * Check whether an IANA timeZone identifier observes daylight saving time. * * - Compares UTC offsets at two dates six months apart (January and July). * - A zone is considered to have DST if its offset differs between the two dates. * - Returns false for invalid or unresolvable timeZone identifiers. * * @param timeZone timeZone identifier to check * @returns boolean indicating whether the timeZone observes DST * * @example hasDaylightSaving("America/New_York") // true * @example hasDaylightSaving("Europe/Berlin") // true * @example hasDaylightSaving("Asia/Tokyo") // false * @example hasDaylightSaving("UTC") // false * @example hasDaylightSaving("Invalid/Zone") // false */ export declare function hasDaylightSaving(timeZone: string): boolean;