module Main where

import Prelude
import Effect (Effect)
import Effect.Console (log)
import Data.Array (length, (!!), updateAt, replicate)
import Data.Maybe (fromMaybe)

main :: Effect Unit
main = do
  -- Here we create an array `a` that will hold exactly 5 Ints.
  -- In PureScript, arrays are not fixed-length, but we can create
  -- one with 5 elements initialized to 0.
  let a = replicate 5 0
  log $ "emp: " <> show a

  -- We can set a value at an index using the `updateAt` function,
  -- and get a value with the `!!` operator.
  let a' = fromMaybe a $ updateAt 4 100 a
  log $ "set: " <> show a'
  log $ "get: " <> show (fromMaybe 0 $ a' !! 4)

  -- The `length` function returns the length of an array.
  log $ "len: " <> show (length a')

  -- Use this syntax to declare and initialize an array in one line.
  let b = [1, 2, 3, 4, 5]
  log $ "dcl: " <> show b

  -- PureScript doesn't have a direct equivalent to Go's `...` syntax,
  -- but you can simply define the array with its elements.
  let b' = [1, 2, 3, 4, 5]
  log $ "dcl: " <> show b'

  -- PureScript doesn't have a direct equivalent to Go's index-based
  -- initialization, but you can achieve similar results with functions.
  let c = [100, 0, 0, 400, 500]
  log $ "idx: " <> show c

  -- Array types are one-dimensional, but you can compose types
  -- to build multi-dimensional data structures.
  let twoD = replicate 2 (replicate 3 0)
  let twoD' = [[0, 1, 2], [1, 2, 3]]
  log $ "2d: " <> show twoD'

  -- You can create and initialize multi-dimensional arrays at once too.
  let twoD'' = [[1, 2, 3], [1, 2, 3]]
  log $ "2d: " <> show twoD''