AppleScript question re return value of whose

DEVONthink Automation
1

This code

tell application id "DNtp"
	set result to (contents of databases) whose name contains "xxx"
end tell

creates a “list of lists” structure in result: One list for each database, and in each of these lists the matching records found in that database:

{{}, 
{content id 82535 of database id 5}, 
{content id 8412 of database id 7, content id 8374 of database id 7, …}, 
{}, 
{content id 2873 of database id 4, content id 5178 of database id 4,…}, 
{}, 
{}, 
{}}

I thought (!) that whose should return a single list, namely of the records it found. Is this return construct a feature of whose or a specialty of DT? In my mind, a list of records would be perfectly fine since they contain a database property.

2

It’s not specific to DEVONthink, in this case whose is applied to a list of lists. And therefore the result looks the same.

3

Thanks for the clarification – the examples I found where only simple ones.

4

.flat() and .flatMap(), are, of course, helpful here in JS.

Or in AppleScript, perhaps something like:

on run
    flatten({{1, 2, 3}, {4, 5, 6}, {7, 8, 9}})
end run


on flatten(xs)
    script
        on f(vs)
            if list is class of vs then
                set n to length of vs
                set a to {}
                
                repeat with i from 1 to n
                    set a to a & f(item i of vs)
                end repeat
            else
                vs
            end if
        end f
    end script
    
    f(xs) of result
end flatten
5

The question originally arose in a JS script :wink: then I saw that the same thing happens in AS.

flat etc would be ok here if it returned a one-level list in all cases, i.e. regardless of the nesting of objects whose is called on.

6

Probably worth experimenting with its depth argument, which defaults to 1, but to which you can supply the special quasi-integer value Infinity.

Array.prototype.flat() - JavaScript | MDN

Infinity - JavaScript | MDN