Week number
Last modification: Monday, August 25, 2008 12:47 amReturns the week number of the specified date.
Function Calls
weekNumber(current date)Implementation
on weekNumber(_dateObject)script Week_Number_Extras
-- Define an extra function to calculate how many days of a week belong to the next year
on daysBelongingToNextYear(_dateObject)
-- Find out how many of the next 6 days belong to the next year
set _currentYear to year of _dateObject
set _daysInNextYear to 0
repeat with _dayOffset from 0 to 6
if (year of (_dateObject + (_dayOffset * (24 * 60 * 60)))) ≠ _currentYear then
set _daysInNextYear to _daysInNextYear + 1
end if
end repeat
return _daysInNextYear
end daysBelongingToNextYear
end script
-- Make a copy of the passed date object to avoid changes to the original
copy _dateObject to _dateObjCopy
-- Save the year for later
set _yearOfGivenDate to year of _dateObjCopy
-- Set the date back to a Monday
repeat
if weekday of _dateObjCopy is Monday then exit repeat
set _dateObjCopy to _dateObjCopy - (24 * 60 * 60)
end repeat
-- Find out how many days of this week belong to the next year
-- If at least 4 days do belong to next year then
-- it’s safe to assume that it’s the first week of the year
tell Week_Number_Extras to set _daysBelongingToNextYear to daysBelongingToNextYear(_dateObjCopy)
if _daysBelongingToNextYear ≥ 4 then return 1
-- Set the date back a week at a time until the previous year is reached
-- Count how many weeks had to pass to reach the previous year
set _weeksPassed to 0
repeat
if year of _dateObjCopy ≠ _yearOfGivenDate then exit repeat
set _dateObjCopy to _dateObjCopy - (7 * 24 * 60 * 60)
set _weeksPassed to _weeksPassed + 1
end repeat
-- Return the week number depending on wether the last monday of the previous year
-- did belong to the first week of this year or not
tell Week_Number_Extras to set _daysBelongingToNextYear to daysBelongingToNextYear(_dateObjCopy)
if _daysBelongingToNextYear ≥ 4 then
return _weeksPassed + 1
else
return _weeksPassed
end if
end weekNumber
