Std.List.maximumOn

fn

maximumOn: &Array[T] -> fn(T) -> K -> Option[T] where K: Ord

This is a callable function.

The element whose key is largest, or None for an empty array.

The text after the name is the type checked by Pudu.
Read arrows from left to right: inputs come first, and the final type is returned.
& borrows a value for this call instead of moving or copying it.
Names inside [ ] are type arguments, such as the item type held by a collection.
Option holds Some(value) or None when no value is available.