Reading a large file? I created an Applescript to read an XML document...

Question

I created an Applescript to read an XML document that had been exported from Final Cut Pro but it has trouble reading anything larger than a 1mb. Even 500kb takes a long time.
My code is most likely very ineffecient, but I have little experience with Applescript. The script reads an XML document one line at a time then breaks down each line into it's componenents and literally reads each character looking for "<name>" then it checks to see if "<reel>" came before it. It then records the name in between "<name>" and "</name>." Then I get my list of tapes that are in the Final Cut Pro project. Does anyone have any advice on how to improve this code?
property type_list : {"TEXT", "XML"}
property extension_list : {"TXT", "XML"}
on open these_items
tell application "Finder"
set my_file to these_items as string
set file_ref to (open for access my_file) read
close access file my_file
set AppleScript's text item delimiters to ASCII character 10
set new_list to every text item of file_ref
set lengthofarray to length of new_list
set h to 1
set shotcount to 0
set finalShots to {"You have ", "", " shots in your project."}
set finalListoftapes to {"Your list of tapes are:", ""}
repeat lengthofarray times
set i to 1
set x to 1
set switch to 0
set z to {""}
set reelName to {"", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", "", ""}
set letter_list to item h of new_list
set AppleScript's text item delimiters to ""
set final_list to every text item of letter_list
set lengthofletter_list to length of final_list
repeat lengthofletter_list times
if item i of final_list is "<"a" then
if item (i + 3) of final_list is "m" then
set letter_list2 to item (h - 1) of new_list
set final_list2 to every text item of letter_list2
set lengthofletter_list2 to length of final_list2
set j to 1
repeat lengthofletter_list2 times
if item j of final_list2 is "<" then
if item (j + 1) of final_list2 is "r" then
if item (j + 2) of final_list2 is "e" then
set x to (i + 6)
set y to 1
repeat while item 1 of z is not "<"
set item y of reelName to item x of final_list
set x to (x + 1)
set y to (y + 1)
set item 1 of z to item x of final_list as string
end repeat
if item 1 of reelName is not "" then
set displayText to reelName as string
set lengthofListoftapes to length of finalListoftapes
set shotcount to (shotcount + 1)
set k to 1
repeat lengthofListoftapes times
if item k of finalListoftapes is equal to displayText then
set switch to 1
end if
set k to (k + 1)
end repeat
if switch is 0 then
set finalListoftapes to (finalListoftapes & displayText)
set check to finalListoftapes as string
end if
set switch to 0
end if
end if
end if
end if
set j to (j + 1)
end repeat
end if
end if
end if
end if
set i to (i + 1)
end repeat
set h to (h + 1)
end repeat
set item 2 of finalShots to shotcount
set finalShots to finalShots as string
set AppleScript's text item delimiters to ASCII character 10
set finalListoftapes to finalListoftapes as string
set finalListoftapes to finalShots & (ASCII character 10) & (ASCII character 10) & finalListoftapes & (ASCII character 10) & (ASCII character 10) & "This list of tapes has been saved on your desktop."
set path_list to these_items as string
set filepath to path_list & "_listoffiles.txt"
set outputFile to (open for access file filepath with write permission)
write finalListoftapes to outputFile
close access outputFile
display dialog finalListoftapes
end tell
end open

Answer 1

Try changing your approach - don't read it into an array, process it one line at a time. Obviously any approach where you have the whole file in memory is going to exceed memory at some size of the file.