Generic Function | Package: util.date-time | ToC | DocOverview | CGDoc | RelNotes | FAQ | Index | PermutedIndex
| Allegro CL version 9.0 Unrevised from 8.2 to 9.0. 8.2 version

## date-time-year

Arguments: date-time

Returns the year (an integer) of the date represented in date-time if that value can be calculated by non-`nil` slots in date-time, and returns `nil` otherwise. date-time must be a `date-time` object.

There is no year slot in a `date-time` instance. This function calculates its value from other slots (such as `ymd-yd-century` and `ymd-yd-year-in-century`). If `nil` is returned, it may be because the `date-time` is not complete (so needed slots are not filled in) or because the date portion is incomplete (needed information is not available, such as when a relative date -- "85-10-10" -- is all that is provided.) In the first case, applying complete-date-time will fill in needed slots. In the second case, it will not.

    (require :datetime)
    (use-package :util.date-time)

    ;; date-time is 1985/04/12 10:15:30, that is 15 and a half
    ;; minutes after 10 AM April 12, 1985.
    (setq a (date-time "1985-04-12T10:15:30"))
    (date-time-year a) -> 1985

See date-time.htm for information on support in Allegro CL for parsing and generating time expressions using the ISO 8601 standard.

Copyright (c) 1998-2019, Franz Inc. Oakland, CA., USA. All rights reserved.
This page was not revised from the 8.2 page.
Created 2012.5.30.

|  | ToC | DocOverview | CGDoc | RelNotes | FAQ | Index | PermutedIndex
| Allegro CL version 9.0 Unrevised from 8.2 to 9.0. 8.2 version