mirrors/Nim
1
0
Fork 0
mirror of https://github.com/nim-lang/Nim.git synced 2026-01-10 15:04:59 +00:00
Code Issues Packages Projects Releases Wiki Activity

Merge pull request #3281 from nanoant/patch/lib-pure-times-hotfix

Browse Source 
times: Export & document countLeapYears/Years/Days
This commit is contained in:
Dominik Picheta
2015-09-03 21:37:35 +01:00
parent a373bdd0c9 ef5f0b1ac9
commit 4fefdb4d91
1 changed files with 17 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

30
lib/pure/times.nim
View File

@@ -1051,26 +1051,30 @@ proc parse*(value, layout: string): TimeInfo =
return info
# Leap year calculations are adapted from:
# from http://www.codeproject.com/Articles/7358/Ultra-fast-Algorithms-for-Working-with-Leap-Years
# http://www.codeproject.com/Articles/7358/Ultra-fast-Algorithms-for-Working-with-Leap-Years
# The dayOfTheWeek procs are adapated from:
# from http://stason.org/TULARC/society/calendars/2-5-What-day-of-the-week-was-2-August-1953.html
# http://stason.org/TULARC/society/calendars/2-5-What-day-of-the-week-was-2-August-1953.html
# Note: for leap years, start date is assumed to be 1 AD.
# counts the number of leap years up to January 1st of a given year.
# Keep in mind that if specified year is a leap year, the leap day
# has not happened before January 1st of that year.
proc countLeapYears(yearSpan: int): int =
(((yearSpan - 1) / 4) - ((yearSpan - 1) / 100) + ((yearSpan - 1)/400)).int
proc countLeapYears*(yearSpan: int): int =
## Returns the number of leap years spanned by a given number of years.
##
## Note: for leap years, start date is assumed to be 1 AD.
## counts the number of leap years up to January 1st of a given year.
## Keep in mind that if specified year is a leap year, the leap day
## has not happened before January 1st of that year.
(((yearSpan - 1) / 4) - ((yearSpan - 1) / 100) + ((yearSpan - 1) / 400)).int
proc countDays(yearSpan: int): int =
proc countDays*(yearSpan: int): int =
## Returns the number of days spanned by a given number of years.
(yearSpan - 1) * 365 + countLeapYears(yearSpan)
proc countYears(daySpan: int): int =
# counts the number of years spanned by a given number of days.
proc countYears*(daySpan: int): int =
## Returns the number of years spanned by a given number of days.
((daySpan - countLeapYears(daySpan div 365)) div 365)
proc countYearsAndDays(daySpan: int): tuple[years: int, days: int] =
# counts the number of years spanned by a given number of days and the remainder as days.
proc countYearsAndDays*(daySpan: int): tuple[years: int, days: int] =
## Returns the number of years spanned by a given number of days and the
## remainder as days.
let days = daySpan - countLeapYears(daySpan div 365)
result.years = days div 365
result.days = days mod 365