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Date & Time

The Date & Time functions expose Velox helpers and selected Delphi runtime operations for constructing, comparing, decomposing, formatting and converting TDateTime values. Use this group when a script needs calendar components, elapsed spans, local or UTC clock values, ISO week information, or an interchange timestamp.

Value model​

Velox scripts use Delphi's TDateTime representation: a floating-point day count whose epoch is 30 December 1899. The integral part identifies a date and the fractional magnitude identifies a time of day. One day is 1.0; one hour is 1 / 24. Values do not contain a timezone, locale or daylight-saving marker.

That model has practical consequences:

  • local, UTC and timezone-neutral values are all the same type, so the script must preserve their meaning;
  • arithmetic does not consult timezone or daylight-saving rules, and direct subtraction has a further pre-epoch trap: Delphi's negative fractional-time convention means raw differences across different dates before 30 December 1899 are not necessarily chronological durations;
  • most Delphi routines work at millisecond resolution even though the underlying Double can contain smaller differences; and
  • values before the 1899 epoch use Delphi's negative-value convention, where the time-of-day is represented by the magnitude of the fractional part.

Choosing an entry​

  • Use CompareDate, CompareTime or CompareDateTime according to whether the calendar date, time of day, or full timestamp matters.
  • Use DayOfTheWeek and the ISO decode functions when Monday must be day 1. DayOfWeek uses the older Sunday-first numbering instead.
  • Use DaysBetween for complete millisecond-normalised 24-hour units. DaySpan preserves a raw fractional difference but requires particular care with pre-epoch values.
  • Use Date for the Velox host's local date and DateUTC for the current UTC date. Neither result records which clock produced it.
  • Treat DateTimeToUnix as a timezone-neutral numeric conversion. The Velox-exposed implementation does not convert local time to UTC.

Important behaviour​

Several entries are direct bindings to the Delphi 37.0 runtime installed with the product, while DateUTC and the script-level DateTimeToUnix have Velox/PascalScript implementations. Similar names therefore do not prove identical overloads or error behaviour. Each child page identifies the actual terminal implementation.

Formatting entries can observe process-wide locale settings. Clock entries observe the Windows host clock. Pure component and arithmetic entries neither attach timezone information nor compensate for daylight-saving transitions. Validate calendar fields before calling low-level routines that index date tables; not every Delphi helper performs its own range check.