Sharing my parser for advent of code 2022 day 11

[ytyubox]

Thanks for this project! I want to feedback on how I parse the puzzle input from https://adventofcode.com/2022/day/11.

With input

Monkey 0:
  Starting items: 79, 98
  Operation: new = old * 19
  Test: divisible by 23
    If true: throw to monkey 2
    If false: throw to monkey 3

Monkey 1:
  Starting items: 54, 65, 75, 74
  Operation: new = old + 6
  Test: divisible by 19
    If true: throw to monkey 2
    If false: throw to monkey 0

Monkey 2:
  Starting items: 79, 60, 97
  Operation: new = old * old
  Test: divisible by 13
    If true: throw to monkey 1
    If false: throw to monkey 3

Monkey 3:
  Starting items: 74
  Operation: new = old + 3
  Test: divisible by 17
    If true: throw to monkey 0
    If false: throw to monkey 1

And the parser

 let parser = {
    let monkey = Parse(MonkeyObj.init) {
      Parse {
        "Monkey "
        Int.parser()
        ":"
      }
      Parse {
        Whitespace(1, .vertical)
        Whitespace(2, .horizontal)
        "Starting items: "
        Many {
          Int.parser()
        } separator: {
          ", "
        } terminator: {
          "\n"
        }
      }
      Parse {
        Whitespace(2, .horizontal)
        "Operation: new = old "
        OneOf {
          Parse(Command.add) {
            "+ "
            Int.parser()
          }
          Parse(Command.time) {
            "* "
            Int.parser()
          }
          Parse(Command.square) {
            "* old"
          }
        }
      }
      Parse {
        Whitespace(1, .vertical)
        Whitespace(2, .horizontal)
        "Test: divisible by "
        Int.parser()
      }
      Parse {
        Whitespace(1, .vertical)
        Whitespace(4, .horizontal)
        "If true: throw to monkey "
        Int.parser()
      }
      Parse {
        Whitespace(1, .vertical)
        Whitespace(4, .horizontal)
        "If false: throw to monkey "
        Int.parser()
      }
    }

    return Many {
      monkey
    } separator: {
      Whitespace(2, .vertical)
    }
  }()

Wish you have a great day! ❤️