Nested Repeat Loops in Applescript - applescript

Question

The following code has two lists: myURLs and myIMGs. I want to loop through the sites listed in myURLs, take a screenshot, then save them in my Shared folder as the file name listed in myIMGs. So, google.com's image will be saved as "google.jpg", and so forth. The list in myIMGs corresponds to the list in myURLs.
This is what I have, but it doesn't quite work. It loads the first URL from myURLs, takes a screenshot of it, but then loops through each file name in myIMGs and saves that one screenshot with all those various file names. Then, it loads the next URL in myURLs and does the same thing. How do I set the file names in the myIMGs list to correspond to the URLs being loaded from myURLs? I'm having trouble with the nested loops.
set myURLs to {"https://google.com", "https://wikipedia.org", "https://bing.com", "https://apple.com"}
set myIMGs to {"google.jpg", "wikipedia.jpg", "bing.jpg", "apple.jpg"}
-- Sets settings of Safari without interfering with user's settings.
repeat with myURL in myURLs
tell application "Safari"
set myDoc to front document
set windowID to id of window 1
do JavaScript ("window.open('" & myURL & "','_blank','titlebar=0');") in document 1
close window id windowID
set the bounds of the front window to {0, 20, 915, 812}
delay 5
end tell
-- Take screenshot, crop and save to Shared folder
repeat with myIMG in myIMGs
do shell script "screencapture -o -l$(osascript -e 'tell app \"Safari\" to id of window 1') /Users/Shared/" & myIMG
set this_file to "Macintosh HD:Users:Shared:" & myIMG
try
tell application "Image Events"
-- start the Image Events application
launch
-- open the image file
set this_image to open this_file
-- get dimensions of the image
copy dimensions of this_image to {W, H}
-- Crops off the Safari header
crop this_image to dimensions {W, H - 50}
-- save the changes
save this_image with icon
-- purge the open image data
close this_image
end tell
end try
end repeat
end repeat

Answer 1

You don't want to use two nested Repeat loops... you want to repeat and increment the variable n and then use item n of each list.
Here's the changed code... tested and works as expected:
set myURLs to {"https://google.com", "https://wikipedia.org", "https://bing.com", "https://apple.com"}
set myIMGs to {"google.jpg", "wikipedia.jpg", "bing.jpg", "apple.jpg"}
-- Sets settings of Safari without interfering with user's settings.
repeat with n from 1 to (count myURLs)
set myURL to item n in myURLs
tell application "Safari"
set myDoc to front document
set windowID to id of window 1
do JavaScript ("window.open('" & myURL & "','_blank','titlebar=0');") in document 1
close window id windowID
set the bounds of the front window to {0, 20, 915, 812}
delay 5
end tell
-- Take screenshot, crop and save to Shared folder
set myIMG to item n in myIMGs
do shell script "screencapture -o -l$(osascript -e 'tell app \"Safari\" to id of window 1') /Users/Shared/" & myIMG
set this_file to "Macintosh HD:Users:Shared:" & myIMG
try
tell application "Image Events"
-- start the Image Events application
launch
-- open the image file
set this_image to open this_file
-- get dimensions of the image
copy dimensions of this_image to {W, H}
-- Crops off the Safari header
crop this_image to dimensions {W, H - 50}
-- save the changes
save this_image with icon
-- purge the open image data
close this_image
end tell
end try
end repeat
You could simplify more by doing things like programmatically setting the file name based off of the URL string, and then you'd only have to maintain one list.