Write a generic function

Place type parameters after a function's name. moon normally infers them from arguments and context. A direct call can write function<Type>(...) when an empty collection or another argument supplies no clue.

The bare angle-bracket spelling is moon's explicit call form. It takes no dot or colon prefix.

fn identity<T>(value: T) -> T { value }

fn first<T>(values: [T]) -> Optional<T> {
  if values.len() == 0 { none } else { some(values[0]) }
}

fn main() {
  println(identity("moon"))
  println(first<int>([7]))
}