Skip to content
Gregorian calendar date library in Common Lisp.
Common Lisp
Branch: master
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Type Name Latest commit message Commit time
Failed to load latest commit information.
src Merge branch 'master' of Apr 2, 2019
t Merge branch 'master' of Apr 2, 2019
.gitignore First commit. Sep 11, 2015 Introduce comparison functions. Sep 13, 2015
circle.yml Add circle.yml Sep 11, 2015


The project is planed to be on top of LOCAL-TIME as its extension later.

Circle CI Coverage Status

Calendar-date is a Gregorian calendar date library in Common Lisp.



Since calendar-date is not on Quicklisp yet, please use its local-projects feature for now.

cd quicklisp/local-projects
git clone

You can install calendar-date via Quicklisp,

(ql:quickload :calendar-date)


[Function] calendar-date

CALENDAR-DATE year month day => new-calendar-date

[Function] calendar-date-today

CALENDAR-DATE-TODAY &key timezone => new-calendar-date

[Function] calendar-date-year

CALENDAR-DATE-YEAR calendar-date => year

[Function] calendar-date-month

CALENDAR-DATE-MONTH calendar-date => month

[Function] calendar-date-day

CALENDAR-DATE-DAY calendar-date => day

[Function] calendar-date-values

CALENDAR-DATE-VALUES calendar-date => year, month, day

[Function] calendar-date-day-of-week

CALENDAR-DATE-DAY-OF-WEEK calendar-date => day-of-week

[Function] calendar-date=, calendar-date/=, calendar-date<, calendar-date>, calendar-date<=, calendar-date>=

CALENDAR-DATE= calendar-date1 calendar-date2 => generalized-boolean
CALENDAR-DATE/= calendar-date1 calendar-date2 => generalized-boolean
CALENDAR-DATE< calendar-date1 calendar-date2 => generalized-boolean
CALENDAR-DATE> calendar-date1 calendar-date2 => generalized-boolean
CALENDAR-DATE<= calendar-date1 calendar-date2 => generalized-boolean
CALENDAR-DATE>= calendar-date1 calendar-date2 => generalized-boolean

[Function] business-day-p

BUSINESS-DAY-P calendar-date => generalized-boolean

[Function] weekday-p

WEEKDAY-P calendar-date => generalized-boolean

[Function] weekend-p

WEEKEND-P calendar-date => generalized-boolean

[Function] next-day

NEXT-DAY calendar-date => new-calendar-date

[Function] previous-day

PREVIOUS-DAY calendar-date => new-calendar-date

[Function] next-week

NEXT-WEEK calendar-date => new-calendar-date

[Function] previous-week

PREVIOUS-WEEK calendar-date => new-calendar-date

[Function] same-day-of-week-of-next-week

SAME-DAY-OF-WEEK-OF-NEXT-WEEK calendar-date => new-calendar-date

[Function] same-day-of-week-of-previous-week

SAME-DAY-OF-WEEK-OF-PREVIOUS-WEEK calendar-date => new-calendar-date

[Function] day-of-week-of-the-week

DAY-OF-WEEK-OF-THE-WEEK day-of-week calendar-date => new-calendar-date

[Function] next-month

NEXT-MONTH calendar-date => new-calendar-date

[Function] previous-month

PREVIOUS-MONTH calendar-date => new-calendar-date

[Function] same-day-of-next-month

SAME-DAY-OF-NEXT-MONTH calendar-date => new-calendar-date

[Function] same-day-of-previous-month

SAME-DAY-OF-PREVIOUS-MONTH calendar-date => new-calendar-date

[Function] first-of-the-month

FIRST-OF-THE-MONTH calendar-date => new-calendar-date

[Function] nth-of-the-month

NTH-OF-THE-MONTH nth calendar-date => new-calendar-date

[Function] nth-of-the-month-in-business

NTH-OF-THE-MONTH-IN-BUSINESS nth calendar-date => new-calendar-date

[Function] nth-business-day-of-the-month

NTH-BUSINESS-DAY-OF-THE-MONTH nth calendar-date => new-calendar-date

[Function] last-day-of-the-month

LAST-DAY-OF-THE-MONTH calendar-date => new-calendar-date

[Function] last-business-day-of-the-month

LAST-BUSINESS-DAY-OF-THE-MONTH calendar-date => new-calendar-date



Copyright (c) 2015 Masayuki Takagi (


Licensed under the MIT License.

You can’t perform that action at this time.