module Aoc

import Prelude

-- `by` is the first argument for use in `map`
nums' : String → String → List Int
nums' by s = map stringToInt $ filter (_/=_ "") $ split (trim s) by

nums : String → List Int
nums s = map stringToInt $ filter (_/=_ "") $ split (trim s) " "

isDigit : Char -> Bool
isDigit '0' = True
isDigit '1' = True
isDigit '2' = True
isDigit '3' = True
isDigit '4' = True
isDigit '5' = True
isDigit '6' = True
isDigit '7' = True
isDigit '8' = True
isDigit '9' = True
isDigit _ = False

indexOf? : ∀ a. {{Eq a}} → a → List a → Maybe Nat
indexOf? {a} z xs = go Z z xs
  where
    go : Nat → a → List a → Maybe Nat
    go ix z Nil = Nothing
    go ix z (x :: xs) =
      if z == x then Just ix else go (S ix) z xs