on map over theList given script:theScript
	set resultList to {}
	repeat with theItem in theList
		set resultList to resultList & theScript's lambda(theItem)
	end repeat
	return resultList
end map

on grep over theList given script:theScript
	set resultList to {}
	repeat with theItem in theList
		tell theScript
			if lambda(theItem) is true then
				set resultList to resultList & theItem
			end if
		end tell
	end repeat
	return resultList
end grep

-- end library

script mapScript
	property HowMany : 0
	
	on lambda(someone)
		set HowMany to HowMany + 1
		return someone & " Gardner " & HowMany
	end lambda
end script
map over {"Mark", "Erin", "David"} given script:mapScript

script grepScript
	on lambda(someone)
		considering case
			if contents of someone is equal to "David" then
				return true
			end if
			return false
		end considering
	end lambda
end script
grep over {"Mark", "Erin", "David"} given script:grepScript