Apply a callback to an array

editable example

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Using map

ghul

use IO.Std.write_line

use Ghul.Pipes

write_line("{$([1, 2, 3, 4, 5] |> map(value => value * value))}")

[1, 4, 9, 16, 25]

Writing apply

ghul

use IO.Std.write_line

use Collections.List

use Collections.LIST

apply[T, U](values: T[], callback: T -> U pure) -> List[U] is

let applied = LIST[U]()

for value in values do

applied.add(callback(value))

od

return applied

si

shout(word: string) -> string => "{word.to_upper()}!"

write_line("{$([1, 2, 3, 4, 5] |> apply(value => value * value))}")

write_line("{$(["frog", "newt", "toad"] |> apply(shout))}")

[1, 4, 9, 16, 25]
[FROG!, NEWT!, TOAD!]