| Allegro CL version 8.2 Unrevised from 8.1 to 8.2. 8.1 version |
Arguments: date-timespec durationspec
Returns a new date-time
object obtained by subtracting
the duration
specified by durationspec from the date-time
specified by
date-timespec.
The default method does not subtract two duration
s.
> (require :datetime) > (use-package :util.date-time) > (subtract-duration (date-time "1985-04-10T10:30:40") (duration "1MT1H4S")) #<date-time "1985-03-10T09:30:36" @ ...>
See duration, date-time, and add-duration.
See date-time.htm for information on support in Allegro CL for parsing and generating time expressions using the ISO 8601 standard. See particularly the section Adding/Subtracting Durations, where it is pointed out (with examples) that adding and subtracting durations are not inverse operations and adding durations is not associative.
Copyright (c) 1998-2016, Franz Inc. Oakland, CA., USA. All rights reserved.
This page was not revised from the 8.1 page.
Created 2010.1.21.
| Allegro CL version 8.2 Unrevised from 8.1 to 8.2. 8.1 version |