Setting a variable one child above in an inline-function

[Steve0Greatness]

Below, I'm attempting to update the value of a variable(that is defined by it's parent) to a value(either the current length being evaluated, or the previous length)

const usage = [
  [ "-y", "Yes to all prompts" ],
  [ "-r", "Recursive" ]
]
fn print_usage() {
  let min_distance = 0
  iterator.range(0, list.length(usage))
  |> iterator.map(fn(i) {
    let evaluation_distance =
      string.length(result.unwrap(
        list.at(result.unwrap(list.at(usage, i), [""]), 0),
        "",
      ))
    case evaluation_distance > min_distance {
      True -> evaluation_distance
      False -> min_distance
    }
  })
  |> iterator.map(fn(val) {
    min_distance = val # <- This says it needs to have "let" before it so that it can be defined... but it already is.
  })
}

[Steve0Greatness]

I found my answer. I'm now using gleam/javascript's reference.

[lpil]

Hey @Steve0Greatness !

You could make the code a little more concise using the list module and using tuples rather than lists within the usage list. It would also be faster as there's no usage of list.length and list.at (which are slow as they need to traverse the linked list) but it doesn't matter for the small input data.

Here's how I might write this:

const usage = [
  #("-y", "Yes to all prompts"),
  #("-r", "Recursive"),
]

fn print_usage() {
  let length =
    usage
    // Get the lengths of each description
    |> list.map(fn(pair) { string.length(pair.1) })
    // Find the longest one
    |> list.fold(0, int.max)
}