3 ms·

In modern JS wouldn't you use an arrow function? someObj.someMethod(something => something);

• didroe 5y ago
  The main advantages of Ruby blocks over that approach are: - they have special control flow that interacts with the method call or surrounding function. ie. calling `break` in `something` can early return from `someMethod`, or calling `return` will return from the function containing the `someMethod` call (blocks use `next` to return from them) - due to using separate syntax / being a separate language construct, there is far better ergonomics in the presence of vargs or default values Take this contrived example for instance: def some_method(a = 42) b = yield puts "Hey #{a} #{b}" end some_method do break end In JS you would have to something horrible like this: const breakSomeMethod = {}; // Could alternatively use an exception function someMethod(one, two) { var f, a; if (typeof one == 'function') { f = one; a = 42; } else { a = one; f = two; } var b = f(); if (b === breakSomeMethod) { return; } console.log(`Hey ${a} ${b}`) } someMethod(() => breakSomeMethod);