Convert an array to a JSON string

I need to convert an array with an unknown number of indices to a JSON string for transmission (which is why it isn't possible to iterate through it using $ORDER). Does ObjectScript provide functionality to convert an array to a JSON string?

Edit 1: As Joel mentioned, the array is subscripted and has an arbitrary structure like:

a(1)="a"
a(3,4)="b"
a(3,6)="c"
a(5,6,7)="d"

which needs to be converted to

{"1":"a", "3":{"4":"b","6":"c"}, "5":{"6":{"7":"d"}}}

I had considered using a combination of $Query (to traverse the array) and $Order (to retrieve property names) but was wondering if a utility method already exists.

IRIS for UNIX (Apple Mac OS X for x86-64) 2019.4.0DS (Build 165U) Fri Aug 30 2019 00:02:44 EDT