Fast handler for finding the index of sublists within a list

Scripting Forums Code Exchange
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#1

Hello.

This only works for N=1, to N=4, I suspsect I can change the adjustment of q so it is valid for larger sublists.

It is all curtsey of Nigel Garvey, he have given the idea, and the raw material so to speak for this. The intention is of course to return the first item with the sought. It will always return the first value, even if there are several instances, sharing that value.

Enjoy!


set a to {{"Apples", 1}, {"Melons", "2"}, {"Strawberries", "3"}, {"BlackBerries", "4"}, {"Blue Berries", "5"}, {"Pears", "6"}, {"Lemons", "7"}, {"Plums", "8"}, {"Bananas", "9"}, {"Mango", "10"}, {"Avocado", "11"}, {"Rasberries", "12"}}

set b to {{"Apples", "1", "fair"}, {"Melons", "2", "fair"}, {"Strawberries", "3", "fair"}, {"BlackBerries", "4", "fair"}, {"Blue Berries", "5", "fair"}, {"Pears", "6", "fair"}, {"Lemons", "7", "fair"}, {"Plums", "8", "fair"}, {"Bananas", "9", "fair"}, {"Mango", "10", "fair"}, {"Avocado", "11", "fair"}, {"Rasberries", "12", "fair"}}

set c to {{"Apples", "1", "fair", "Foreign"}, {"Melons", "2", "fair", "Seedy"}, {"Strawberries", "3", "fair", "Wild"}, {"BlackBerries", "4", "fair", "Foreign"}, {"Blue Berries", "5", "fair", "Foreign"}, {"Pears", "6", "fair", "Foreign"}, {"Lemons", "7", "fair", "Foreign"}, {"Plums", "8", "fair", "Foreign"}, {"Bananas", "9", "fair", "Berry"}, {"Mango", "10", "juicy", "Tasty"}, {"Avocado", "11", "nut", "eggsy"}, {"Rasberries", "12", "Cherries", "frabolicious"}}



set res to indexOfItemN("Rasberries", a, 2)

set res to indexOfItemN("Plums", b, 3)

on indexOfItemN(item_a, the_list, n)
” © McUsr and put in Public Domain. Don't post this as it is elsewhere, or put it into a Public Accessible Repository or Library
” You may use it as you see fit otherwise, but please refer to this post for reference: http://macscripter.net/edit.php?id=155921
	local astid, p, q
	set astid to AppleScript's text item delimiters
	set AppleScript's text item delimiters to return
	set the_list_as_string to return & the_list & return
	set AppleScript's text item delimiters to return & item_a & return
	if (the_list_as_string contains result) then
		set p to (count paragraphs of text item 1 of the_list_as_string)
		set q to p mod n
		if n = 3 and q > 1 then set q to q - 1
		if n = 4 then
			if q = 2 then set q to q - 1
			if q > 2 then set q to q - (n - q) - 1
		end if
		set AppleScript's text item delimiters to astid
		if (p is 0) then return 1 -- Catch modern paragraph count for empty text
		return (p div n) + q
	else
		set AppleScript's text item delimiters to astid
		return 0
	end if
end indexOfItemN

Edit

Ran back, reset text item delimiters, for the case when we don’t find the substring.

#2

Hello.

I actually thought I had tested every possibility, but this fails for elements at even positions in sublists with three items.

I am trying to establish the pattern to write a general solution. :o

#3

Hello!

It works perfectly for sublists with no more than 4 items in each! :o.

When I eventually should need to find the index of stuff in sublists larger than that, I’ll post an update.