problem.js

class Foo {
  constructor(name) {
    this.name = name;
  }

  callMeByMyName() {
    return this.name;
  }
}

const logTheImportantReturnValueOf = fn => console.log(`Super important log: ${fn()}`);

const foo = new Foo("Yasyf");
console.log(foo.callMeByMyName()); // "Yasyf"
logTheImportantReturnValueOf(() => foo.callMeByMyName()); // "Super important log: Yasyf"
logTheImportantReturnValueOf(foo.callMeByMyName); // Uncaught TypeError: Cannot read property 'name' of undefined