x12TimeCodeOffset

Container free time, demurrage, billing deadlines, bill of lading dates and EDI timestamps.

Signature

x12TimeCodeOffset(timeCode: X12OffsetTimeCode): string

Read the UTC offset an X12 time code (data element 623) states.

Data element 623 is the code beside the date (element 373) and time (element 337) of an X12 AT7, G62 or DTM segment, and the only thing in the segment that says where the clock was. 31 of its 56 codes state an offset; this function reads those. The element’s own definition: “Code identifying the time. In accordance with International Standards Organization standard 8601, time can be specified by a + or - and an indication in hours in relation to Universal Time Coordinate (UTC) time; since + is a restricted character, + and - are substituted by P and M in the codes that follow”. Codes are release 008010, read from Stedi’s X12-licensed dictionary; the X12 text itself was not reached. ### Time codes that state an offset

Codes	The dictionary’s definition	Offset
`01`–`12`	“Equivalent to ISO P01” … “P12”	`+01:00` … `+12:00`
`13`–`24`	“Equivalent to ISO M12” … “M01”	`-12:00` … `-01:00`, counting down
`25`–`29`	“Equivalent to ISO M2:30”, “M3:30”, “P5:30”, “P9:30”, “P10:30”	`-02:30`, `-03:30`, `+05:30`, `+09:30`, `+10:30`
`UT`	“Universal Time Coordinate”	`+00:00`
`GM`	“Greenwich Mean Time”	`+00:00`

13–24 count down: 13 is -12:00 and 24 is -01:00. The code rises as the offset nears UTC, so 20 is -05:00.
25–29 were added in release 006010 and are not valid in an 004010 or 005010 interchange. The function takes no release, so it reads them.
GM is +00:00 by a GMT rule, not by X12’s statement. X12 defines it only by the name “Greenwich Mean Time”. UN/ECE Recommendation 7 ¶12 names one scale by both names, “Co-ordinated Universal Time (formerly known as Greenwich Mean Time)”, so GMT reads GM as UTC.
A named code returns "": X12 states no offset for ET, ES, PD or LT, and GMT holds no table of zone offsets. Read one with x12TimeCodeZone.
To get the instant, resolve the segment’s local date-time at the offset: resolveLocal(parseX12DateAndTime("20240615", "1430"), x12TimeCodeOffset("20")) is "2024-06-15T19:30:00Z".
For a code that arrives as a string, call classifyX12TimeCode first: its "offset" result carries the code narrowed to this function’s parameter.
Matching is exact: two characters, upper case, no padding. Returns "" for a code that is not one of the 56 and for a non-string. Use isValidX12TimeCode to check a code.

Parameters

Parameter	Type	Description
`timeCode`	`X12OffsetTimeCode`	X12 data element 623 time code (e.g. “20”)

Returns

the offset as ±HH:MM, or "" on invalid input

X12OffsetTimeCode

Examples

import { x12TimeCodeOffset } from "@northguild/gmt/intermodal/parse";

x12TimeCodeOffset("20") // "-05:00"

Source

intermodal/parse/x12TimeCodeOffset.ts