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When constructing a time table for os.time, the isdst flag can be set to true, false, or omitted to indicate daylight‑saving status for the given local time. The Lua reference manual does not define what happens when the supplied local time is ambiguous (e.g., 1:30 am during a “fall back” transition) or skipped (e.g., 2:30 am during a “spring forward” jump),
Goal: reliably detect or handle ambiguous local times that occur twice during DST fallback when using TimeZones.jl's ZonedDateTime constructor, to prevent silent misinterpretation of timestamps. Constraints: the solution must preserve backward compatibility for existing code that relies on the current default (earlier occurrence), avoid adding runtime overhe
Ambiguous DST times in Qt When a local wall‑clock time occurs twice during the fall‑back transition, Qt must decide which UTC offset to apply. The default is to use the earlier offset, but this choice is not formally guaranteed across operating systems or future Qt releases. Unix‑like hosts query the IANA time‑zone database while Windows historically consult
Goal: Verify the exact offset PHP selects when a DateTime representing an ambiguous local time (e.g., 01:30 am during a fall‑back transition) is converted with setTimezone to a zone that observes the same offset, and whether the result is consistently the earlier offset. Constraint: This behavior is not documented as a rule and may vary with timelib updates;
Context AlmaLinux relies on the IANA Time Zone Database packaged with glibc, and administrators set the system zone via timedatectl set-timezone or by updating the /etc/localtime symlink. Applications perform date conversion by reading the TZ environment variable or the system zone. Unresolved behavior During a daylight-saving transition, a local timestamp s
Django's timezone framework converts naive datetimes to UTC for storage when USE_TZ=True , assuming they belong to TIME_ZONE . During daylight-saving fall-back transitions, a local time such as 01:30 can occur twice, creating an ambiguous instant. The documentation acknowledges this overlap but does not define a deterministic resolution rule for django.utils
tzinfo local-seconds-to-utc offset policy at DST fallback Goal: Convert a regional wall-clock time, for example 01:30 on a fall-back date in America/New_York, to a UTC instant using Racket's tzinfo collection. The local-time-to-UTC mapping is not one-to-one around daylight-saving changes. A repeated local time can correspond to two UTC offsets, while a skipp
When converting a naive datetime to an timezone‑aware DateTime in Elixir, the goal is to correctly handle ambiguous times that occur during daylight‑saving‑time fallback transitions without introducing an external dependency such as Timex. The standard DateTime.from_naive/3 function resolves ambiguity by defaulting to the earlier offset and does not expose a
Handling Regional Time Zone Conversions When converting regional date and time data to a UTC-based NSDate , Objective-C provides two primary paths: NSDateFormatter for string-based parsing and NSCalendar with NSDateComponents for programmatic construction. The DST Transition Constraint A critical challenge arises during Daylight Saving Time (DST) transitions
lua
qt
django