2つの日付の期間を日本語表記でていねいに返す

AppleScript名：2つの日付の期間を日本語表記でていねいに返す

— Created 2016-01-17 by Takaaki Naganoya
— 2016 Piyomaru Software
use AppleScript version "2.4"
use scripting additions
use framework "Foundation"

–Date Difference
set sDate to "2016/1/15" –Japanese Date format "YYYY/MM/DD"
set eDate to "2016/1/20" –Japanese Date format "YYYY/MM/DD"
set aDiffStr to retDateDiffStr(sDate, eDate, "/", "/", "", "〜") of me
–> "2016/1/15〜20"

–Month Difference
set sDate to "2016/1/15" –Japanese Date format "YYYY/MM/DD"
set eDate to "2016/2/20" –Japanese Date format "YYYY/MM/DD"
set bDiffStr to retDateDiffStr(sDate, eDate, "年", "月", "日", "〜") of me
–> "2016年1月15日〜2月20日"

–Year Difference
set sDate to "2015/12/15" –Japanese Date format "YYYY/MM/DD"
set eDate to "2016/1/20" –Japanese Date format "YYYY/MM/DD"
set bDiffStr to retDateDiffStr(sDate, eDate, "年", "月", "日", "〜") of me
–> "2015年12月15日〜2016年1月20日"

–2つの日付の期間を日本語表記でていねいに返す
on retDateDiffStr(sDate, eDate, ySeparator, mSeparator, dSeparator, diffSeparator)
　　
　　set sDateO to date sDate
　　set eDateO to date eDate
　　
　　set diffY to (year of eDateO) – (year of sDateO)
　　set diffM to (month of eDateO) – (month of sDateO)
　　set diffD to (day of eDateO) – (day of sDateO)
　　
　　set sYstr to (year of sDateO) as string
　　set sMstr to (month of sDateO as number) as string
　　set sDstr to (day of sDateO) as string
　　
　　set eYstr to (year of eDateO) as string
　　set eMstr to (month of eDateO as number) as string
　　set eDstr to (day of eDateO) as string
　　
　　if diffY > 0 then
　　　　–Year Difference
　　　　set outStr to sYstr & ySeparator & sMstr & mSeparator & sDstr & dSeparator & diffSeparator & eYstr & ySeparator & eMstr & mSeparator & eDstr & dSeparator
　　else if diffM > 0 then
　　　　–Month Difference
　　　　set outStr to sYstr & ySeparator & sMstr & mSeparator & sDstr & dSeparator & diffSeparator & eMstr & mSeparator & eDstr & dSeparator
　　else if diffD > 0 then
　　　　–Date Difference
　　　　set outStr to sYstr & ySeparator & sMstr & mSeparator & sDstr & diffSeparator & eDstr & dSeparator
　　end if
　　
　　return outStr
　　
end retDateDiffStr