Question

delete_at only takes a single index. What’s a good way to achieve this using built-in methods?
Doesn’t have to be a set, can be an array of indexes as well.

arr = ["a", "b", "c"]
set = Set.new [1, 2]
arr.delete_at set
# => arr = ["a"]

Answer 1

One-liner:

arr.delete_if.with_index { |_, index| set.include? index }