This Commented CUE demonstrates how to use the built-in function list.SortStrings to sort lists of strings alphabetically.

file.cue
package example

import "list"

unsorted: ["B", "C", "A"]
sorted: list.SortStrings(unsorted)
TERMINAL
$ cue eval
unsorted: ["B", "C", "A"]
sorted: ["A", "B", "C"]