What is the raku equivalent of the JavaScript arrow function?

Question

In JavaScript, I can go

const materials = [
  'Hydrogen',
  'Helium',
  'Lithium',
  'Beryllium'
];

console.log(materials.map(material => material.length));
// expected output: Array [8, 6, 7, 9]

I guess that raku has some chops in functional - and I wonder if someone can clarify the equivalent code (see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions )

Answer 1

The most direct equivalent would be

my @materials = <Hydrogen Helium Lithium Beryllium>;
say @materials.map(-> $material { $material.chars });

but an arrow sub is more explicit than you need in this case, because

say @materials.map: *.chars;

would also be sufficient (method call on a "whatever star" returns a code block that calls that method on its argument), and

say @materials».chars;

would also work (hyper-application applied to the dot operator).