2Dリスト内の要素のうち最多のアイテム数を求める

AppleScript名：2Dリスト内の要素のうち最多のアイテム数を求める

— Created 2017-10-01 by Takaaki Naganoya
— 2017 Piyomaru Software
use AppleScript version "2.4"
use scripting additions
use framework "Foundation"

set aList to {{1, 2, 3, 4, 5, 6, 4}, {1, 2, 3, 4, 5, 6}, {1, 2, 3, 4, 5, 6, 0, 0}} –7,6, 8 items
set aRes to getMaxItemCountFrom2DArray(aList) of me
–>　　8 –max items is 8

on getMaxItemCountFrom2DArray(aList)
　　set anArray to current application’s NSArray’s arrayWithArray:aList
　　set eRes to (anArray’s valueForKeyPath:"@unionOfObjects.@count")’s valueForKeyPath:"@max.self"
　　return eRes as integer
end getMaxItemCountFrom2DArray