Since we're on the topic of higher order functions, arrow functions allow you to express function currying very succinctly (which some people prefer). This is a contrived example to illustrate the syntactical differences:

  const arrow = (a) => (b) => `${a}-${b}`
  
  function verbose(a) {
    return function (b) {
      return `${a}-${b}`
    }
  }
  
  function uncurried(a, b) {
    return `${a}-${b}`
  }
  
  const values = ['foo', 'bar', 'baz']
  values.map(arrow('qux'))
  values.map(verbose('qux'))
  values.map(uncurried.bind(null, 'qux'))
  values.map((b) => uncurried('qux', b))