How can I limit the number of results returned by an expensive filter expression in AppleScript?

Question

In my Apple Notes automation on macOS Big Sur, I’d like to load any 5 notes whose name contains a substring. For example, if I know that I actually have 5 notes that match the query, I can write something like this:

tell application "Notes"
  set matches to id of (notes 1 thru 5 in default account whose name contains "a")
end tell

This runs relatively fast (< 1 second on my account with thousands of notes), because it terminates as soon as it finds those 5 matches and doesn’t look any further. For comparison, a query without such "1 thru 5" clause (or a count query) times out before it even returns any results, which is understandable. However, my problem is that if there aren’t enough (i.e., fewer than 5) matches, the query will error without returning any results:

Notes got an error: Can’t get notes 1 thru 5 of default account whose name contains "a". Invalid index.

Thus, my question is whether there’s a way for me to get "at most 5 results" in a single query?

Answer 1

Thus, my question is whether there’s a way for me to get "at most 5 results" in a single query?

No, it cannot be done in a single query.

If you want to loop through a given count downwards then the following example AppleScript code is how I'd do it:

set maxNumber to 5
set searchString to "a"

set matches to missing value
repeat with i from maxNumber to 1 by -1
    if matches is equal to missing value then
        try
            tell application "Notes"
                set matches to id of ¬
                    (notes 1 thru i in default account ¬
                        whose name contains searchString)
            end tell
        end try
        if matches is not equal to missing value then exit repeat
    end if
end repeat

return matches