Question

in this code:

class MyClass
  myfun: (arg) ->
    for x in arg
      do ->
        ...

the scope outside of the loop is MyClass, while inside of the loop (it’s an anonymous function) the scope changes to the DOMWindow.

Why does this happen? How can I prevent it? My main problem is that I can’t access other functions inside the MyClass class if the scope changes.

thanks

Answer 1

Use the fat arrow syntax to bind the a function to the current context:

class MyClass
  myfun: (arg) ->
    for x in arg
      do =>
        ...

This happens because the do keyword just calls the function without any context, so it defaults to the window object.

do -> ...

Is equivalent to

(function() {
    ...
}());