gistfile1.txt

export function format(value, formatter) {
  const formatted = formatter(value);
  return formatted;
}

function formatString (value) {
  return value.toUpperCase()
}

function formatNumber(value) {
  return value.toFixed(2)
}

const hello = format('hello', formatString);
console.log(hello); // "HELLO"

const pi = format(3.14159, formatNumber);
console.log(pi); // "3.14"

// This version should throw a type error
// const invalid = format(true, formatString);
// console.log(invalid);